Some extra bits of advice about the backups:

– Test them. You don’t have a backup if you can’t actually get the data back 🙂
– Just having everything in Dropbox doesn’t count, if you delete a load of stuff locally, getting it back through the dropbox interface can be painful.
– Make sure it’s as automated as you can make it. The more work you have to do to back it up the less likely you will be to do it.