Sorry about that - same problem happened again over night.
It was the hard disk filling up, causing the mySQL errors.
Last time, the server tech thought the problem was solved by cleaning out a bunch of extraneous files. Worked for a while...
So we're going to need some scheduled downtime to switch to a new, larger partition. It'll take about 30 minutes, and will (preferably) happen at night or early in the morning EST.
Forums read button... probably not. That's a vBulletin bug. We recently applied a vB patch, and if it wasn't fixed, it'll hopefully be in the next release.
The biggest problem was the tech admin wasn't answering his phone(s). We left messages for him by every method we have (about 5), and unfortunately he didn't check until the end of the day. I even tried to track down his mom (she moved - couldn't find her).
Apologies for the down time. You can bet we'll be making sure this doesn't happen again.