If you've been looking for a live wallpaper that offers up a bit of functionality and nice physics, then Gravity Home may fit the bill perfectly. It's a live wallpaper / launcher hybrid, and unlike some of the competitors in the Market, it's actually useable.
The concept behind Gravity Home is simple: instead of having static icons on your homescreens, why not have icons that dynamically move around as your device moves? While this may sound slightly annoying, the icons actually "float" around the homescreen, so the movement is very slow and fluid, making it easy to tap the one that you want while it's still moving around.
This wallpaper is free in the Android Market, and you can grab it by hitting the widget below.