Captain Skyhawk posted this over at DCEvolution

First happy easter from all of us at DC Evolution! What's is a better time than now to tell you we have hidden some easter eggs in our images. The contents of the easter eggs vary from a video, games and a new theme. We have hidden the eggs in the following images:

Simon BO-nus editon,
Tetris 2 OverClocked and
DCGNUBoy GBSPlay

If you find one, than take the credits by posting where and how you can found them in our forums.

A hunting tip: they can all be find trough our menu on the Dreamcast.