Every once and awhile I make sure to check to make sure my backups are in place, sufficient, and running. It is also a good idea to go through a restore once and awhile too to make sure you know how to actually do a restore and also so you know that the process you have in place actually works.
If you do not have a backup system in place – there is no excuse. Stop what you are doing and at least take a look at something like Jungle Disk. You can easily backup your data (automatically) online for a cost that that is worth every penny.
Seriously – stop what you are doing and take 5 minutes to think or re-think about your backups.