The most interesting feature for me would be the cooling added bonus. It got to be nice. But then, at one point the liquid must get warm, I presume.
Hmm, isn't cooking oil (or some similar oil) one of the ingredients of lava lamps? Now there is a visual.... rather than sink/float non-mixing liquids, how about different colored, non-mixing liquids being stirred by the cooling fans?
Hmm, I will have to look into this (ooh, look - bright, shiny).