Yeah, i've tried that - can't really say it worked well - self-illumination radiosity takes insane amount of time to tweak.
Right now, the best results i have are from gradient map (see picture), but it still doesnt look right - not even close...
http://www.eccentrix.com/members/z80180/room.jpg
(this is just a light setup test render - all geometry is going to be different. Lit by a skylight with light tracer)