I was at university, and Farmville was all the rage on Facebook. My girlfriend wanted me to play because it'd mean she'd be able to trade stuff with me or something (I forget why exactly), and I eventually caved in.
After ten minutes of playing it, I was bored. I couldn't really judge people that would click plants hundreds of times, several times a day, though, because I played World of Warcraft. It was just a more interesting type of grinding...
I figured out that in order to grind through the game most efficiently, I'd need to plant Tomatoes every two hours, so I wrote a bot that would:
1. Spin up a VM.
2. Open the browser to Farmville.
3. Open up an automated clicking application I had written that worked on Flash.
4. Find the outermost vegetable patch.
5. Click in a 20x20 grid (or however big the whole area was).
6. Replant, and close.
I didn't tell my girlfriend about the bot, and I'd turn it off when I went to visit her, so she was shocked when she went on my farm to see that I was a higher level than her. I'd jokingly feign ignorance, saying that I was just playing it like her, until one day when I had left the script running and she saw my farm picking itself while I was studying.