What about an old GBA lite, GBA with Afterburner installed on it or a GBA micro?

Like what kind of LED power or light do you need behind the screen?

Having a modded GBA that could play on a 100" background would be awesome.

Sorry if I'm slightly derailing your topic here.

By the way, have you ever thought of something like this?

http://youtube.com/watch?gl=US&hl=en...&v=8eFvo6HqpK4

No electronics needed.