Android phones already keep their contacts, settings, and app choices synced and backed up, but what about your SMS and call records, your application data, and other Android essentials? There are ways, and the Tested blog runs down the best of them.
Actually, the best way to back up literally everything on your Android phone is to "root" it and install a third-party firmware, like CyanogenMod, that contains a full system backup and restore functionality, like Nandroid. Then again, to get your phone rooted, you'll need to wipe it entirely, so it's something of a Catch 22. How-to blog Tested suggests a few other means of backup up your Android data, beyond the stuff (contacts, settings, app choices) that are generally backed up, with some quirks, by Google.
Tested's choices include the Astro File Manager for backing up those apps that allow it, Sprite Mobile Backup for putting your SMS and call records onto services like Dropbox or an SD card, and tactics like the previously mentioned Calltrack calls-on-a-calendar tool to keep all the ephemeral data of your mobile life handy and accessible. Those sound like pretty good choices, too. We would also suggest creating an account at AppBrain to keep tighter track of your installed applications, as Tested notes that Google's background backup of your installed apps is finicky, and limited to Android 2.0 and above.
Have you found a great, comprehensive Android backup solution, in one or more Android or desktop apps? Tell us about them in the comments.