Free; paid upgrade avaialable; $19.95 to buy
Publisher's description of DeskScapes
Stardock DeskScapes is a program that allows users of Windows Vista to have animated wallpaper on their desktops. What makes DeskScapes special is that it supports the .DREAM format (first seen with Windows DreamScene) which supports dynamic animated wallpapers that can use virtually no CPU. The free version includes 4 high quality animated wallpapers that are configurable.