As an result of gene engineering experiment were to created fluorescent green mice. The gene which produces the glowing protein is from a species of jellyfish. These mice are really neat looking creatures and I'd like to buy couple of them.
Also in other case create in China scientists managed to expressed red fluorescent protein.
As well it is possible to make only the eyes glow. I bet here are a lot of people that will want to do the same with themselves :). If only it was possible to do that with humans ...
Sources: Forbes, Discovery Magazine