Tim,
I wouldn't discount the possibility of a denial of service (DOS) attack, but I also wouldn't panic and take an axe to the hard drive.
(I do have a poster on the wall depicting an angry duck who says "Compute this!" as he initiates a violent act against his recalcitrant machine, but this is more for venting my own frustration than as a model for my own behavior ;-)
I'm intrigued by the periodic shutdown phenomena, and I really appreciate your efforts at using perl to open the oyster, so to speak. There's precious jewelry to be found somewhere in Wikipedia's innards, and you're just the man to find it.
Ed Poor Cheerleader, Coach and Vendor of Refreshments
P.S. May I fax you a fresh, hot cup of coffee?