Yes, the box crashed last night. Yes, currently SMTP is down and I'm not sure why (smtpd is crashing with a signal 11 all of a sudden). Yes, this will all be fixed (in theory) tonight between 3:30 and 6pm PST.
I don't know why this rash of hardware problems has cropped up, but I'm going to guess it's that the box is overheating a bit, or the RAM isn't that good, or the poor little thing is just taking an enormous beating. At this point I don't care because between 3:30 and 6:00 tonight the box will go down, have it's innards put in the new (actually old) system and have that fresh, new and lovely clean box come up.
I'll put a page on my home website of http://arcterex.net/blog with a list of what is working and what isn't, and encourage all to post there (or here if apache is up) to let me know what is working and what isn't. Please expect a couple of days of confusion before things are worked out, but by tonight mail and web at minimum should be up and going for the most part.
So backup, cross your fingers and send good vibes!