My 2.5 year old baby girl got me good. She was in the bedroom with the PC running and on the floor. (We were packing up to move.) When I went in there, the XP login screen was up, but I had it logged in.
I rebooted, and it said it failed Boot due to a bad overclock! WTF did she do? I don't know, but I set it up again and everything is fine.
Gotta love it! Maybe one day she will be better with these things then me! Maybe she already is!