What is a good, cheap, 3D part modeling program?
Searching the web I only found all kinds of open source programs that are not "professional" enough. I am looking for something cheaper than 100$. Anybody knows about one? Thanks.

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http://www.alibre.com/products/hobby/
Its 200 USD, but about the best offering I've seen in that price point.
It can be extended to the Expert version, with simulation, CAM software etc etc