Quote - I'm trying to make a room look as if its being lit only by the light from a TV.  I have a feeling that this could probably be accomplished by using HDMI, IBL, BFD, MOUSE,... or some other acronym that I know very little about.  ;)
Any help along these lines would be greatly appreciated.

If the TV is made up of separate parts, the best way would be to use an anything glows on the screen, then turn ambient light off under scene in the instances panel and remove or turn off light one (the default light Carrara creates when you open a scene.)  Then make sure that indirect lighting is on in the render settings panel.
If the TV is one piece, cleate a fully transparent spline object in the shape of the screen and place it directly in front of the screen, touching it if possible.  Then just use an anything glows on that object as above.