Hard lesson, expensive lesson. And one you never want to learn the hard way. Do you backup your computer daily? How much would it cost you if your computer crashed RIGHT NOW? What files would you need for that big deal that’s coming up tomorrow?

If you haven’t been backing up then you need to run, don’t walk, to buy an external hard drive that’s at least as big as your computer drive as well as some kind of backup software. We’re a Mac shop, so system 10.7 has Time Machine built in which does hourly backups, but before that: Super Duper and Carbon Copy Cloner were our backup software of choice.
And, while it’s good to have a backup handy right next to your computer – what if your building burned down? Do you have a backup offsite?

There are remote backup services available that can backup your computer over the internet at night, but just remember it will take a while to upload the files.
While tape drives used to be a great option and give you multiple versions of the backup, they are also slow. Besides, with the size of harddrives going up fast and prices coming down all you need a couple of external hard drives to keep your data safe.
Large offices can have a central server to store critical info, and have it all backed up centrally or on a redundant drive.

One neat trick for really important stuff is to e-mail it to your Gmail account, which has lots of space.

Something to think about next time you’re working on a huge project.