I remember people coming up with transparent backgrounds for programs writen in VB6. The idea has been around for a while, but I guess there is a reason why it didn't take off.

The quickly moving colours triggers some people. Similar to flashing lights but less extreme. I’ve heard them call it “ants moving across the screen”. That doesn’t mean it isn’t a good design though, just that it isn’t universal. If an app/game /os can only have one theme, it must be universal.