Macbook
I use my macbook for personal, school and some work stuff, I consider it my most important machine, and it contains a lot of important files to me, including all the archive of projects I’ve done in the past1. I rely on Time Machine to do daily backups of my hard drive (and that can be restored in a couple of hours). I also do weekly/monthly backups to my Desktop and my Network Drive.
VPS
I own a VPS that runs all of my websites. It has a cron script every day that backups to disk the mysql databases, and it backups the important folders every week. Then I rsync it to my macbook and it’s replicated the same way.
I rely on Google to save my email. All my email accounts go to my gmail account, even my alcidesfonseca.com email. So there is always a copy on the original server, and another in Gmail.
Cloud “stuff”
Twitter, Delicious, Flickr, Google Reader OPML, Contacts, etc… I like to have a backup copy in my hard drive every month. I have some scripts for some, for others I just go to the website and download it. If your delicious account is as important for you as it is for me, you should also download it.
1I’ve lost my archives from the pre-2005 years, and I know the pain it has given me. Your past projects are really important for you as a programmer.