Well, it looks like we’re back up, at least to some degree. I managed to convince Tom to head in to the colo and open it up for me, so I could look at the box. It looked like a random crash, and booted up just fine after hitting the big red button. I replaced the RAM with some from my workstation (only 384 meg left!) just in case this random lock up (and others in the past) have been cause by bad RAM.
So things are mostly back to quasi-normal, or at least usable. Lets just hope it stays up for more than 24 hours this time!