A customizeable involute scroll pump.
The virtue of this type of pump is that it allows for a very good compression, non-slipping pump in a very compact space. Which is why they are commonly found in things like air conditioners and heat pumps.
Also, the way the spirals mesh is pretty mesmerizing, so may be useful in hypnotizing an army of zombie slaves... but you didn't hear that from me. ;) ;)
More details, TODO's, and sexy animations are on my full article, here: