A few years ago I had a page on my website about how to use a certain open source library on Windows, since the maintainers didn't want to/couldn't provide support for Windows. Then a few months later, out of the blue, a guy emails me and says 'listen, I need a small program for Windows that does X, Y and Z and they are all related to the library you have on your website, can you write me a quotation on how much it would cost to develop this'. This guy wanted it for personal use; I did a back of the envelope calculation and it came into about 5 or 8 hours of work. I wanted to be paid a commercial fee of about 70 euros an hour at the time, but I figured that this guy wasn't going to pay several hundreds of euros for a small toy for personal use. It looked like a nice, interesting, small project though, so I basically told the guy 'here's the deal, I don't really have time to write this program and I don't want to commit to anything that I can't live up to. But, I will write this program for you and then release it as open source. The catch is that any time I put into this project is going to be time that I don't get to spend with my girlfriend. So what I'm asking you in return is that you think of a nice present for my girlfriend, she likes X, Y and Z, to make up for that.'
The guy was very surprised but after talking it over with his wife (brainstorming for ideas I guess) agreed. So I wrote the program, went back and forth with him a few times until it did what he wanted; had to switch libraries because the one I had on my website didn't work so in the end I think I put in about 10 or 12 hours. The guy was very happy with the result, I send him a version that did what he needed and then we left on vacation, and I sort of forgot about it.
A few weeks later we came home and there was a small wooden box waiting for us; at first I didn't know what it could be, then I cracked it open and it had an iPod for my girlfriend (this was a few years ago when they were still several hundred euros) and a bottle of very nice champagne for the both of us, and a note saying how much he and his wife had appreciated the program and how they hoped we'd like the gifts.
Per hour I don't think I made that much, but it felt much better than any of the money I've ever made from the odd job through elance :)