A quick-n-dirty solution knocked up in Lazarus for playing a video as a wallpaper on the Windows platform. The program was inspired by Wallpaper Engine.
The code is a little messy and I didn't really have the time to polish it up, but the barebones are there and the basic functionality is working as expected.
Here's a working website where binaries can be downloaded: Official VideoDesktop website.
- libVLC and its Pascal wrapper