I should think pretty much everyone knows this one..
http://www.blender.org/
3D modelling and animation tool, it also has a very nice video editor embedded in it!
Xnormal, this does certain things better than Blender, producing better quality normals, height, ambient occlusion.. It's a very nice set of tools
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http://www.xnormal.net/1.aspx
BlackSmiths 3D paint.. Paint directly on to your model! It's nowhere near photoshop (for which there is a plug-in to do this..droooool.. at nearly two hundred quid
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http://www.blacksmith3d.com/blacksmith3 ... ftware.php
The freeware version of 3Dpaint is buried in the download that you can only find once you've registered
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Ooh yeah! One of these was real hard to dig up.. Mix your normal maps!
http://www.planetinaction.com/software/ncombiner.htm
Ooh! Free tiling filter tools!
http://www.filterforge.com/download/
They're at ze bottom!
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