After having used it for a few weeks I really ought to mention Mozy , partly to try and get some extra storage space, but mostly because it’s a very interesting service for both Windows and Mac OS X users. I’ve only used the Beta release Mac client, but running it on my 1GHz G4 Powerbook has been relatively painless. About 2 times out of 30 backup runs I’ve noticed it was active, but the rest of the time I’ve been pleasantly surprised at just how up-to-date it’s kept my files – far more recent than any manual system I’ve ever used.
You can choose to use their own encryption key which will allow you to buy DVD’s of data from them should you have an absolute catastrophe, or enter your own which disables the DVD option but means your data remains private. The free account offers 2GB of storage, and so far I’ve only found 1GB of data that I really wouldn’t want to be without, and the initial upload can take some time depending upon your bandwidth, but I’ve set the client to run after 5 minutes of inactivity which means that the updates are small and fast. It typically updates between 1 and 4 times per day (hmm, am I online too much ?) and has a web based restoration service which allows you to browse through some recent snapshots (timestamped for the server time zone, unfortunately).
I’m seriously considering the paid for service (4.95 USD/mo) which allows unlimited storage space, as this would allow me to put all of my RAW image files a long way offsite for 26.33 GBP/yr (at today’s exchange rate, buying two years at once). The question I’ve asked myself is: “If you have 100GB of image files, how much would you be prepared to pay to recover from a total hard drive failure ?” Of course, downloading that much might break your ISP usage allowance for one month…
 If you use this link to sign up, you will get an extra 250MB of storage space, as will I. See, it’s not totally selfish.