If you are part of those people who are reluctant to upgrade to newer kernels, here is an example of how this can make your life miserable every 209 days.
There is a specific kernel bug in Lucid that will provoke a kernel panic after 208 days, which is regular behavior on a server (and a cloud instance ?). Here is the kernel GIT commit related to this :
This has been fixed in the ubuntu kernel since 2.6.32-38 months ago but if you prefer not to upgrade to earlier kernels on Lucid, you will be hit by this bug.