>Well, I truly know what you mean, having several times thought I had completely "unbreakable" apps, only to have some user break it somehow, even after considerable QA testing. Of course, I'm also proud to say I have "broken" many apps done by other people, too, and slightly enjoy sending crash-bug reports to other developers :)

You'd be amazed how much you can accomplish on a computer fair just walking around and pressing enter once on each keyboard. Back in early nineties, wherever I did that, half of the software displayed actually crashed right away (unless the keyboard was unplugged, which was often the case).