I didn't spend anything to get BitCoin equipment, but I'm still slightly miffed that its recent increase in popularity has brought such a quick ramp in the difficulty factor that my 5770 won't see returns in months.

I've actually quit mining because the excitement of a chance of getting a winning block is now offset by the worry of having the video card 'burn out' before it pays for itself. (Also, the winter's over and the extra hot air from the computer's exhaust are no longer welcome.)