A new Fast Food place opened near my work. My mother-in-law got me a gift card to the place as a birthday gift. I went on opening day and tried to use my gift card, they said the system wasn't in place yet and just gave me my food for free. This worked for almost a month. It was the best gift card I ever had! Started with $20 on it and I got at least $100 worth of food.

My old apartment complex had a soda vending machine at the pool that was broken. If you put in 50 cents and pressed the button, nothing happened. If you put in another 50 cents and pressed the button, nothing happened. But if you put 50 cents in a 3rd time and pressed the button, you'd get 3 sodas. I could see the vending machine from my couch. So I would watch for someone to try, and then try again, and then give up without trying a 3rd time. And then I'd head over and get 3 sodas for 50 cents. .

Back when physical media video rentals were still a thing, we were gifted a Blockbuster gift card for a free rental. The card proved to be unbreakable. Everytime we rented a movie I would hand the clerk the card. They would scan the bar code on the card, hand the card back, and the movie was free. We used the card for about 3 years until our local Blockbuster closed. There was obviously some sort of software error, but the gift card was never rejected.

When my baby was in the NICU for two weeks after birth, I realised if I waited for about 30 seconds, the hospital car park barrier would just open without me having paid. Saved a lot of money.

For a year I lived in a house in London that was split into three flats. The landlord had submitted meter readings before I moved in, so I just waited for each new bill to put my name on the accounts. When we moved out, I went to submit the meter readings and couldn't figure out who was supplying our gas (heating and cooking). Couldn't find any bills, couldn't see any payments from my bank accounts, it was a mystery. Ended up just calling suppliers asking if they had an account for my address. In the end it turned out that whilst three meters had been installed for the flats, only two had ever been registered. Without a contract with a supplier (or even any readings for the years the flat had been there), there was no way we could be charged for our year's usage - or for the few weeks until we moved out whilst a new account was set up. As the guy from the gas company said to me "Congratulations - you have free gas!" The annoying thing was that we'd kept the thermostat down during the winter to save money. Went totally wild for those last few weeks though.

Found a website where you had to vote for best diving liveaboard company. It was shared by a company in the competition trying to boost the votes. The first prize was a dive trip in the Maldives for 1 week on their liveaboard. I found a flaw in the voting system and asked the company trying to win if they counted individual votes as entries or 1 person gets 1 vote. They replied that each vote counted as an entry. Politely told them to prepare me as the winner. The flaw in the website was that it used simple cookies to check if someone has already voted. Made a script to vote and clear cookies - rinse and repeat. I had a great trip scuba diving for a week in the Maldives!

When in highschool there was a company that offered money to run an advertising window at the top of your screen. It would monitor mouse movement to track whether you were at your computer and pay a small amount per hour. A buddy and I downloaded it and a mouse moving software and would run both 24/7, except when we were on the computer. Made a few hundred dollars off of it before the company closed down.

I used to work for Sears as a teen. When someone came in without the rewards program, I would just put my own info in. That way my sales percentage for rewards members didn't drop, and I got all of their points. The amount of coupons and free money was insane, especially when I was working back in the tools department. I didn't stop until they started upgrading their ancient point-of-sale system. I also had an employee discount of 20% on softlines (clothes, home, etc) and 10% on hardlines (tools), which they didn't take away for a few years after I quit.

I learned before my ASAF basic training to say that I played an instrument whenever they ask the group on the first day. I raised my hand and lied, "the cymbals." So most days I got to angrily smash cymbals together in the air conditioned band trailer, instead of marching/drill practice in the San Antonio summertime sun.

Buffalo Wild Wings used to have a check-in thing. Check in enough times and you get a free meal. The office I worked in was close enough, geographically, that I could check in from there without physically going to the restaurant. A bunch of coworkers and I had an alarm to check in every day and then once we all had the free meal, we’d go there for lunch. I got probably 4 or 5 free meals out of it before BWW revamped that system.

Had a college professor that insisted on doing all tests and quizzes online. If you looked at the page through 'View Page Source' all of the answers for each multiple answer question had a marker on which one was correct.

For a while, you could buy $1 coins from the US Treasury using credit cards. They would ship them to you for free. If you had a rewards credit card, let's say an airline one, you could buy thousands of dollars of coins. Go to a bank, deposit them, and then pay your credit card back. It was a good way to get a ton of points for flying without ever paying for anything. They stopped doing this.

When I was in middle school, Pepsi did a thing where if you bought a 20oz soda, there was a decent chance the cap would say you were a winner on the inside, and you could exchange it for another 20oz. Problem is, a dark colored soda like Pepsi is reflective. Hold the bottle slightly tilted and you could look at the reflection of the inside of the cap. For a whole school year I didn't pay for soda. Bought a winner, and every day I'd exchange the cap at a gas station I passed on the way home for another winner. Eventually Pepsi caught on and instead of it saying you won on the cap itself, there would be a code you had to enter online. We didn't have the internet in our pocket in those days (and it wouldn't have been worth it to read and enter multiple backwards codes for a soda if we had) so this ended the scheme.

Coca Cola did a campaign where you registrar a code from the bottle cap and earn prizes. I worked at a store with bottle deposit and "earned" myself a sweet mp3 player with room for 5 songs or something. I was the only one I knew that had a mp3 player, so it was pretty sweet at the time.

Work allowed us to skip breaks and bank them, but the contract language basically made it so you could bank both 15 min breaks each day, as well as bank your lunch if you never technically clocked out. So I'd just eat while driving from job to job, and bank an hour a day. Was able to use all that time after a while to take an entire month off of work, paid, without even using any of my assigned PTO. HR got pissy about it and tried to rake me over the coals when I got back, but I pointed out the contract language and they realized their hands were tied. They pushed out a new contract to fix this exploit, but my work contract was still good for another year, so I declined and kept banking time, taking time off when I wanted. Of course they didn't offer me a new contract once mine was up, but I had a better paying job closer to home lined up already anyway, and took the last 2 months off, paid, while I started my new job, so I was basically getting 2 salaries.

McDonald’s app uses to give out free ice coffee with 1 dollar purchase. After doing this daily they finally nerfed it to 5 dollar purchase for free ice coffee.

Back in the late 90's with the dot com boom there was a web site called Prize Point. You would play one of their many games, when the game was over you would hit a cash out button and win tickets that was based on your score. My computer was running slow with dial up internet and I was frustrated and hit the cash out button a whole bunch of times. The next thing that popped up was I reached my daily limit of point, something I had never done before. I started doing this everyday and reached the daily limit with just 1 game. The tickets were used like raffle entries for one of their prizes, 1 ticket= 1 entry. I saved all of mine for months and dumped them into a trip to Hawaii. It was one of my best vacations ever.

Taco Bell had a $5 box deal to win a PS4 before it was released to the public. I found that towards the end of the promotion you could enter to win without purchasing a $5 box. You could only enter once per pone number and address... Also the rewards were time based, every 15 minutes someone would win. I woke up every night at 3:16 am and entered 4 times, using my home, work, and my Mother in Laws home and work numbers and addresses. After about a week I was about to stop AND I WON!!!! I had a PS4 3 days before the public could even buy them. The next year I did the same thing and won a second PS4 for the kids game room. After that they changed the rules slightly to make it much harder to game the system.

About 25 years ago Microsoft had a training program where you would take tests for points depending on your grade. You could use those points for free stuff. The loophole was that if you answered a question wrong, you'd lose your points and it would tell you the correct answer, so you could press the back button, fix your answer, and resubmit. I had gotten myself a bunch of shirts and hats, and even managed to get an ink jet printer before they caught on.

Not intentionally, but I discovered after the fact that a $29 bottle of local wine at the market wasn’t on clearance for $6, it was a mistake in the system. It was really good and I probably bought 6 bottles or so over three-ish weeks. .

Not me, but my roommate in college. Whenever you paid for anything on the university's website you'd earn "college bucks". Each year's tuition paid for something small like a beer coozy, fold up lawn chair, or if you somehow spent an absurd amount, an official school-branded kayak. Well my buddy found out that the points were added to your account BEFORE payment went through on the website. So he just refreshed the page over and over and got millions of points. I only found out his scheme when I came home to an entire living room filled with boxes from our school! There were shirts, coolers, chairs, cups, and of course the kayak. We opened all of it (like idiots) and had a giant laugh at the school's expense. All of the guys living in that house were having a great time until we opened the smallest box which had 1000 $100 Visa gift cards. Then we got scared. A bunch of school-branded c**p from a warehouse was probably unusual, but not something that would bother the person loading all that up for delivery. The gift cards though? That was where he got caught. The gift card issuer called the school to verify such a large amount before activating the cards and THAT raised a lot of red flags in the accounting department. They traced it all back to my roommate and came and took everything back (they left the opened items and the worthless gift cards) and suspended him during his final semester of college. He had to write an apology letter and do community service for the school for that whole semester in return for not pressing charges for fraud. It makes for a great story though, and we had a ton of beer coozies and gift cards that we threw at each other like ninja stars.

I’m a traveling RN and on one particular assignment the cafeteria staff was under the impression that travel nurses ate for free. Anything we wanted and as much as we wanted. So for almost 6 months I got all of my meals for free and I also picked up extra stuff for my friends on the unit. Eventually they sent out a hospital wide email stating that we absolutely do not eat for free and never was supposed to get free food so that ended that.

I used to buy the teacher's edition of textbooks. Tests and quizzes in the back. Lazy teachers never changed a thing. Nobody ever found out.

No one ever found out, but they didn't know how to set up Unix when I was in college. You could drop to the parent directory in programming classes, and go into the other classmates folders see how they were coding their projects. Just in case you couldn't figure out a section of your code...

I once got a CatDog piggybank by clicking their online game’s “next” button repeatedly for more points. It was the second prize, but it was the neatest thing ever.

My college had a "points" based meal plan. 100 "points" equaled approx. $6.50. We used special credit card swipers that were able to swipe our IDs when using these points. Midway through my first year, they decided to install self serve kiosks that could give you cash back. If you swiped your card as if you were going to pay, asked for cash back on the kiosk, and then canceled the transaction on the special swiper before it went through on the main kiosk, it would give you cash without deducting the points. So basically free money. As far as I could tell, nobody found out I was doing it because I never saw any point deductions from my ID card and nobody ever talked to me about it. I made about $300 for free. They disabled the cash back option after a couple weeks though.

I bought something from Dollar Shave Club once, my order came and I thought that was the end of that. But 2 months later I got another package from Dollar Shave Club filled with stuff, razors blades, handles, shave butter, face wash etc. I checked all my credit cards and had no new charges from DSC. I kept all the stuff they sent and moved in with my life 2 months after that I got another package of razor blades from DSC. One day I was looking though an alt email account and found some emails from DSC alerting me to update payment information and shipping confirmation. Turns out I had made another DSC account prior but for some reason someone else's order and credit card information was linked to my account. Their CC# was no longer valid and this is where the loophole begins. Every month DSC would try to process a subscription order for razor blades. It would fail because the CC# on the account wasn't valid, but the month after that it would complete the order, maybe because there was an order from the previous month that wasn't fulfilled. So every other month I would get razor blades from DSC. I started adding a bunch of stuff like hair gel, face wash, etc. This went on for 2 years before they realize.

Company I worked for had an employee benefit called a “Lifestyle Account” basically it was a $500 per year reimbursement allowance that could be used on anything related to health/fitness/personal enrichment. The company was very flexible with the rules and you could get away with buying all kinds of things with it. The money would not roll over to the next year if you didn’t use it though. Every year I would buy myself an Apple watch for $500, screencap the receipt, cancel the order and then collect the $500 reimbursement.

Free sandwiches from CFA based on location. Used gps spoofer and got tons of free sandwiches a week on multiple accts. I think I got about $5000 worth of sandwiches and nuggets before they banned me.

Was told in my first day on the job at six flags that our till could be $25 off each day without anyone noticing or caring.