You need to backup. It is not a question of if your computer will fail, but of when. Protect yourself from losing a crazy amount of time by backing up.

Some good options include:

MozyPro backup (online backup ) is just over $5 a month if you don't have much data (less than 5 GB).
Burn cd's if you have to. $.25 each.
Burn DVDs (up to 4.7 GB or more) for $.50 each.