I just finished a new model and rig for a Classic human male figure, which I’m making freely available:
http://www.rchoetzlein.com/art/man/man.htm
There are lots of free rigs out there for toons and monsters (e.g. Tiny, Alfred, Katsumi), but I wanted something basic to allow others to experiment with natural human animation. Feel free to try it out. The link above describes the features and limitations of the rig.