Several years ago I worked with Jim Hunt of PhoneThemes supporting his development of the PhoneThemes Media Player. This allows short video clips or animations to play in a continuous loop, in conjunction with the devices current theme or skin setup.
Now there is quite a library of PhoneThemes to choose from, plus a PhoneThemes Studio toolkit to enable you to create and publish your own themes.
The themes are easily installed on your device. Once you've purchased and downloaded the theme - contained in a CAB file - this is easily installed on the device (you run the 'cab'). Then you switch your device desktop image to the theme and activate the animation. PhoneThemes player connects via GPRS to servers on the Internet to validate the purchase. This is one place where DRM works seemlessly. The PhoneThemes player is included in each theme download in case you don't have it - so one simple download to get it all.
The PhoneThemes player is very well written reacting to the power state changes of your device - so when your backlight goes off it stops playing and using battery.