I don't know if this is specific to my iMac or just the alignment of the planets, but I had an odd moment this morning. I put my iMac (late 2007 20" aluminum @ 2.4GHz) to sleep yesterday evening, and when I tried to wake it up this morning nothing happened. None of the keyboard keys did anything, and touching the power button didn't either. Even holding the power button had no effect. But the machine was warm, indicating to me that it was not just shut down (and I checked the power cord and source), so I knew something was wrong. I unplugged the keyboard and then pushed the power button, and surprise! It started.
I'm thinking that my keyboard got stupid for some reason, but I can't figure out how or why. Has this happened to anyone else? Can someone explain the mechanism involved in this sort of thing?