The thing with a TimeCapsule is that it backs up all the time – you don’t “do” anything to make it happen. I had a portable hard disk for a while and I found my personal backup habit was rather ad-hoc and I went a long time between backups. Since getting the TC, it just happens and when I spilled Lemsip on my MBP, allI had to do with it’s replacement was answer “yes, I have a Time Capsule backup I would like to use” at the appropriate place and I had all my files and settings back in no time…
If you have MobileMe, too – then they really shine. The disk appears on your MobileMe registered Macs all the time, wherever you are in the World and you can download files, even print to it if you really want.
If you have two Macs, you can even remote control the one left at home. Even it it is left on standby – the TC will wake it up for you – even over wireless on newish ones…
Rachel