I lost my job before I even had it.
In the space between my acceptance of the offer and the start date, the company was sold and all new hires (meaning me, since there are only 2 staff members in Australia) were put on indefinite hold.
The strange thing is, I can't say I'm surprised. The boss was pretty flaky, like a freshly baked croissant. Every interaction I had with him had something weird going on.
Not that he's alone: I am amazed at the number of employers who tell me they'll call me two days after the interview... and I never hear from them again. Would it kill them to pick up the phone and say, "Never mind, we're not interested after all?" Even worse is when I hear from a different recruiter that they're still trying to fill the same position... months after they didn't call me back. You know, if they had hired me, instead of still looking for a employee they'd have their problem solved by now.
But that's only half the companies. The other half are perfectly reasonable. I just wish I could figure out which ones are the flakes before the interview, instead of after.