Everyone, I'm very sorry for the outage today.
Our server was hijacked and put into a botnet. Several of the critical system services were replaced with malicious versions leaving me little choice but to reinstall the entire server. But this is why we have backups right? The attacker did not access our database. It seems they just wanted to use our bandwidth.
If they did access our database, all of our passwords are hashed and salted, though, if you use particularly simple passwords it would be a good idea to change them.