The VPS this site is hosted on has a tendancy to kernel panic since I upgraded the kernel to 2.6. I'm not sure why, and the ticket I opened requesting help was replied by someone saying I should check the console. Fat lot of good that did me when this site was down for a few hours.
Help is at hand however in the shape of Mark Ferlatte who mentioned that adding the following to /etc/sysctl.conf and running sysctl -p will make Linux reboot after 5 seconds! Adjust to taste:
kernel.panic = 5
Hopefully we'll have less downtime here.