This is the first image I did to teach myself how to depect a light shinning through a window. Of course, as I found out, it is very simple to do. All you have to do is make your spot light a Halo! That's all there is to it. You have to play around with the lamp settings a little to get everything looking real. I did not mess with any of the lamp settings here and it really seems to give off a nice smoky fill. All you need a is some flames on the other side of the room, an insurence agent close by and the rest, as they say, would be history. If you really want to go for the smoke feel, a marble or noise texture to the light. To get rid of the smoke, sharpen the edges of the halo and decrease it's size. Even cuttting back on the brightness can give nice effects.