Every month I stuff my maya folders into empty smarties tubes, wrap them in cling film, and slide them into carcasses of dead rats, then dig mass graves in my garden and bury them.

Ok admittedly i was just trying to spice up the subject, the truth is that I'm completely lame and never back up anything, and thoroughly regret it when my computer dies randomly. Do yourself a favour and buy an external drive that you can back up to every time you work on something. ie. save to both a C: and D: drive.