I'm not sure if most have seen this but the "Starfield" free live wallpaper in the app store is the best live wallpapers I have seen. I don't typically like to even run live wallpapers because of its effect on overall speed but for showing off your phone its worth the download.
YouTube - Starfield 3D Live Wallpaper - Nexus One
YouTube - Starfield 3D Live Wallpaper - Nexus One