Worm Gear. and 24 Tooth "Tree Top" Gears. Lego Technic compatible. ( Don't know what else to call them.)
These are 2 of the full kit over at http://www.badbrick.com
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In our 3D catalog under Gears.
Didn't want to double post a bunch of gears.
In MakerWare, I modify the "Medium" settings:
I use the Medium Profile with minor adjustments.
Quality: Layer Height = 0.12
All other defaults are the same.
The finer you print them, the better they will be.
Triangle file, and some sanding would help them work and fit a little better.