I found a couple of threads over in hardware issues that suggested it was a a battery problem but I don't think mine is battery related. This problem happens only when I leave the PC on overnight so I usually just don't do that anymore. But last night I had to because I was dowloading an album from Amazon that was taking forever. This morning, the date is something crazy (like the year 1099; each time it's not the same year but it's centuries ago each time) and it errors everything on my system. Nothing starts up, my external hard drive can not be found and so on.
It's easy to fix - restart in safe mode, adjust the date and restart. But what is causing this? I assume a virus of some sort BUT I run Norton once a week and Norton is also on whenever the computer is on "watching" or whatever it does for viruses.