I couldn't resist at least one try with one of the objects as a glowing light source. I turned off the one spotlight in the test scene and set the material of the large ball to have Ambient of pure white and Ambient Value of 5.0. After a couple of aborted test renders, it was clear that the scene would take quite a long time so I set it to go overnight. (Sleep!) Unfortunately, the power cord came out overnight - I blame one of the cats - and the laptop hibernated. I was able to finish the render, but the render time became meaningless.

I seem to have guessed a bit too low on the render settings. It probably needs a factor of three or four on Samples, or a bit higher on the IDL ISS  and even more render time.

As I understand it at this point, this effect is calculated purely for the diffuse light. If somebody wants a project and has lots of patience, they could try to see if another object with fairly high and narrow specular reflection values would actually reflect the glow.

Whichway