You may already know what it was like to travel in a Boeing 747 in the 70s—all glamour with plenty of space to walk around, drink, eat and socialize—especially for those flying in first class. Back then, flying first class was reserved for VIPs and celebrities, and would cost about $550 US from New York to London, which today would equal to about $3,200 US. And free upgrades? Those were almost non-existent, but that didn’t last.

In 1981, when American Airlines launched its frequent flyer program—rewarding their travelers with free upgrades and discounts on future flights—racking up miles for a bump up to first or business started to become “a thing”.

And here are the stories that made those programs boom and ultimately bust due to select individuals taking advantage of the system.

Pudding

the pudding guy

(Image source: Snopes)

In the late 1990s, movement to rack up miles for free upgrades boomed thanks to David Phillips, a.k.a. “The Pudding Guy”. He racked up over 1 million American Airline miles by collecting Healthy Choice pudding bar codes. He spent $3,000 USD on pudding, which amounted to about $150,000 worth of miles. Needless to say, he earned Gold Status for life.

Coins

frequent flyer U.S. Mint

(Image source: NPR)

In 2008, the U.S. Mint started a “direct ship” program where travelers began to purchase the coins with their credit cards, earn miles from U.S. Mint, and then return the coins for a full refund but still keep the miles. There was even a man that ordered more than $2,400,000 USD worth of dollar coins amounting to tens of thousands of miles.

A representative from the U.S. Mint said, “It’s not illegal…But it’s an abuse of the system. That’s not what the system was set up to do. The system was set up to promote the use of dollar coins and we are simply trying to do the right thing here.”

In 2011, the Government closed the program because too many people were taking advantage, some more so than others.

Credit Cards

airline credit cards

(Photo: F. Martin Ramin/The Wall Street Journal)

After the U.S. Mint, travelers obsessed with free upgrades began to find ways to rack up miles via credit cards. Manufactured spending became extremely popular, where travelers purchased something that’s the equivalent of cash such as gift cards, money orders, and other items with a credit card that earns you miles and/or points. The goal is to rack those up and then quickly convert the gift cards, money orders or other cash equivalent items to pay off the credit card.

Nonetheless, credit card companies and airlines caught on, and many have tightened up their terms, changing the amount miles you can earn for certain purchases. Nonetheless, many people continue to find ways to hack through the many systems in place, some even make it their full time job!

(This story first appeared on Travel + Leasure.)