Poseray
http://mysite.verizon.net/sfg0000/

This is mainly intended as a utility to allow various 3D model formats to be rendered in PovRay, but it has other uses, for example you can convert a range of 3D formats to OBJ (+MTL), which Poser & Daz fans would find useful. Also corner angles can be set so the aforementioned progs don't smooth the model into a blob.

Lithunwrap
http://files.seriouszone.com/download.php?fileid=198 (but also on various mirrors)

A `donateware' UV mapping tool that preceded Ultimate Unwrap. It's no longer supported by the software's author, but is still available. Can import and export most common formats, so it's a good reliable converter even if you don't want the UV mapping. You can select polys in your model from a flat map or using the Open GL viewer.