I know a guy....
Bought a 150mW green diode on e-bay.... Not too expensive if one knows how power it properly. He's a turbo-electronics geek so got it working in a sustainable CW, but certainly not portable fasion. Bought one of those Radio Shack lightshows built for a dinky red LASER and put the Green through it. Quite a brillant display from what I hear.
I had a little chat with him this summer when we were discussing this topic. You know, about not waving the green beast thing around the sky especially since he lives near an airport.....