iPodBackup is a shell-script-turned-application (via Platypus) that backs up your home folder to your iPod using the open source backup utility called rsync.
You can customize a list of items to be excluded. By default, the Music folder, as well as certain cache folders are skipped, in order to prevent duplicating your music and because caches are a kind of stupid thing to backup.
The MethodShop Spin: Awesome app..works fantastic, but not sure how practical this may be. Other than a few files here and there I don’t see to many people backing up there home folders if they have substantial gigs worth of data. I already loved rsync, but this is definitely a great accessory.