If you don’t have Dropbox installed stop what you’re doing and install it.
For those not “in the know”, Dropbox is free a cloud based backup/psedo-versioning system. And it’s awesome, oh, and it’s free. Note: I really like Dropbox but Google Drive, SpiderOak, box.com, Microsoft SkyDrive, and BitTorrent Sync are all good alternatives. The important thing here is to backup your files! I also use Dropbox to keep my 3D modeling software in sync, here’s how I do it.