"I worked for a large telecom company back in the day. We had a corporate get-together in Vegas one year. On the sign-in website, there was one of those Wheel of Fortune spinner things, with a button to click it. There would be only one winner of the $10,000 grand prize. But you could spin as many times as you wanted, and there were lots of other smaller prizes, from $5 to $100, plus a couple of other things like dinner gift certificates and shopping cards.
Theoretically, you couldn't just keep spinning all day. There was a built-in delay between clicking the 'Spin' button and when the cheesy wheel animation came to a halt. So most people gave it a few tries and gave up.
I, on the other hand, did not. I wrote a quick little script to click the Spin button, wait, click again, wait, etc ad infinitum, and then opened a gazillion browser windows to run it in. And I left it running the entire weekend we were at the company function. By the time we checked out, I had racked up over $100K in $100 hits, got hundreds of gift certificates, and won the $10,000 prize ten times!
Unfortunately, when the company high muckity-mucks found out about it, they did not take it as the 'light-hearted prank' it was meant to be. I was accused of 'hacking' and 'abuse of corporate computer systems.' My boss's boss's boss had a new butt hole ripped in him, which in turn made him feel obligated to rip a new butt hole in my boss's boss, which in turn and eventually ended up in the creation of my own secondary sphincter.
The only thing that saved me is that I had let a lot of people in on the joke, so it was 100% provable that I wasn't trying to steal anything. Pretty much everyone at the function, at least at my level, had known about it. It became something of a legend, actually.
In the end, they let me go with the verbal reprimand. I never got the $100K, or even $10K (nobody else got the grand prize either). I did get a stack of restaurant gift cards in intercompany mail about a month later, though. That was worth about $500 or so, so it wasn't a total waste of time."