This server was down for about half an hour today as I managed to hose my Ubuntu installation with an upgrade.
The simple apt-get upgrade command functioned as expected, but after a reboot I was no longer able to connect to my server, nor was the apache server accessible either. This coincided with the realization that backing up the VPS before the upgrade would not have been a bad idea. Too late for that.
Thankfully I have a fantastic VPS host (TekTonic), and Jason from support managed to sort everything out in a matter of minutes. I wish I could tell you what he actually did, but all he mentioned was that no devices were being detected and he just tweaked some config files.
If you need a virtual private Linux server, I'd definitely recommend TekTonic. At $15 a month and excellent support, you can't go wrong!