Free Quake 1 Player/Monster Models
 

I use a modified version of mdl23ds to extract geometry from the .mdl files in the shareware version quake .pak files. These then get imported directly into pepakura designer. The initial unfolding usually doesn't correspond very well to anatomical features (e.g. legs, arms), so I modify the unfolding so that it does. After this, I export the unfolding as postscript, and make a .PDF.