So: I entertained an intrusive thought and got a projector to use as a slightly outside-visible mood lighting. This is a bad idea. Here are things usable with it.

Renders:

• Base.
• First test, might as well be festive. (vaguely halloween)
• First draft of random rainbow coloring. Ended up too washed out from the outside, but looks real nice.
• Second draft of random rainbow.
• First christmas
• Random rainbow once more.