Actually, I believe I remember a BIOS setting that can be armed to power a computer on at a desired time and date.  This was in maybe 1 or 2% of the computers I've worked on in the past though.  A low level virus like that, is quite a rarity, but they do exist as far as I know.  The issue is, the virus would have to be programmed into the CMOS chip, and you can't just "add" a virus to the CMOS chip, the whole thing has to be reflashed with the bug included.  Since the hard drives are not spinning, and the RAM dumps as soon as the comp is turned off, CMOS is the only possibility.

Now, for the more likely, less paranoia inducing possibility
On standard ATX power supplies (and all proceeding versions), the power on feature is controlled by a temporary completion of a circuit between two wires (usually smaller wires, green and black).  If a conductive piece of dust could have landed anywhere in there, that could initiate power on sequence.  Same with bugs, or even a well placed drop of condensation.

Before you go to sleep, turn the computer off, and bang on it a couple times.  If it is a conductive contaminant, this is a good way to dislodge it.  Unplug it completely from the internet, then go to bed.  If it turns on, a CMOS virus could be the issue.  If this is true, be very very very happy you unplugged it from the internet, because whoever put the virus on there desperately wants what's on your hard drive. 

There are so many rogue anti malware programs that there are websites online to inform potential victims:

http://www.spywarewarrior.com/rogue_anti-spyware.htm#trustworthy

It's not surprising you got infected at Facebook, social networking sites are prone to problems 

Maybe you have WoL enabled on the bios settings? (WoL, wake up-on-lan, the computer will start up when sent the right kind of packet)

Maybe put a humidifier by it and see if it turns on, and then keep it dry and see if it still turns on... be an interesting test IMO.

WOL?

Wake on lan? my box has this mind you its newish and high speced - prots like that are rarly in storboughts and dell's.

Ive had this happen befour, dosent help having a helicopter as a computer 
Ie FUCKLOADS of fans

On a side not how many of you guys truecrypt.....
I wanted to make a firefox plugin where one can set the temp data, fav, bookmarks etc to be stored in different folders, and then incorperate this with a usb that is trucrypted and have a roming style interface set up, where a button is pressed to enable seedy mode (ie drug mode), a box pops up, slap the trucrypt password in and one is presented with a different profile, ie different history, bookmarks rarara, when seedy mode is disabled, goes back to normal resumes normal history normal bookmarks etc.......

Pipedreams, however for this wasp, id love to do it I can code but spend too much of my day dreaming about drinking from beakers.
if there are coders out there who would find this an interesting project please talk to me about it.

i can iso you an xp sp2 cd ? the next question is where to put it? i may be able to upload it to some online storage i have? how quick do you need it?

These links might also bee helpful:

http://www.petri.co.il/windows_product_activation_after_system_repair.htm

http://www.petri.co.il/what%27s_the_recovery_console.htm

http://www.petri.co.il/install_windows_2000_xp_2003_recovery_console.htm

http://www.petri.co.il/what%27s_system_restore_in_windows_xp.htm

http://www.petri.co.il/recovery_and_troubleshooting_options_in_windows_xp.htm

http://www.petri.co.il/disaster-recovery.htm

http://www.petri.co.il/disk_management

and this particular knoppix CD is loaded with a lot of useful tools for disaster recovery:

http://www.ultimatebootcd.com/

 

Data recovery due to problems with Windows is very common, can you hook your hard disk up to another computer so your Master Boot Record isn't involved and disk swapping doesn't further corrupt your data ? Knoppix based CD's such as Ultimate Boot Disk allow one to access one's hard drive without booting up the operating system, and can fix other problems sometimes    It's critical to back up one's data, and having alll of one's files on the same partition as the operating system is a recipe for disaster  Some other freeware data recovery tools can be found at:

http://free-backup.info/data-recovery-software.htm

 

Thanks but I no longer have adobe so I can not read PDF's until I get that all straightened out.

Ok that works great.. One step closer to achieving a functioning computer.