Turbine/Impeller

A little parametric turbine. The openscad program is quite adjustable.
I was not at all scientific about designing this. I just designed it look somewhat good. There are probably many ways to make it more efficient.
It spins quite well if you blow into it or hold a balloon to the inlet.

You can see a quick video of it here: http://www.flickr.com/photos/53725866@N07/5417888910/