Have no money and need fancy 3D modeling software? If that's your situation, you're in luck: Autodesk is now offering a free preview of their Inventor Fusion 3D modeling software.
Inventor Fusion is Autodesk's tool that unites both parametric and direct modeling approaches, hence its name, "Fusion". The new version incorporates some very cool features, including an automatic model simplification wizard.
The preview won't last forever, however. The Windows version expires on April Fool's day, 2013, while the OSX version strangely expires on New Year's Day, 2013. Yes, you heard that right - there is actually an OSX version!