I'm an independent computer game developer and I try to make games that are interesting and unique.
I like games that are made from simple elements, where those elements interact to create complexity. I find that using physics in gameplay can be a way of acheiving this kind of emergent complexity.
Simple rules that combine to create complex behaviour is something that's around us everywhere. The rules that describe heat transfer, air movement, evaporation, and condensation are well known and simple. But can you tell if it will rain in a month from now?