This archive contains some .blend files that may be interesting
on the topic of radiosity in game blender

dome5.blend
A dome with four hallways leading out from under it
Ready for radiosity calculation

dome5_calcG00d_textured2.blend
the previous file with the radiosity calculated, and
textured.  On layer 2.  If you wish to see no textures
go into shaded mode [ctrl] + [Z].  On layer 1 is the same
model lit by a single lamp, converted to vertex colors (not
textured)

CastleRooms3.blend
An 'E' shaped little room thingy ready for radiosity calculation

CastleRooms3_calculated.blend
previous file with radiosity calculated

CastleRooms3_calculated_nodoubles_someLight.blend
Demonstrates a method of combining light sensitivity with radiosity.  
The readme in it explains more

CastleRooms3_calculated_nodoubles_someLight_textured.blend
previous file, but textured, and including what would happen if just 
the faces after radiosity were made light sensitive on layer 3
