Sculpting correctives "end of chain, tangent space"

Lip Service (plugin for Maya) shows nice corrective approach for skinned model

http://www.youtube.com/user/joealterinc#p/u/0/tWfgyXzr6rU

MPC on youtube

check out for some Making Of stuff from MPC vfx:
http://www.youtube.com/mpcvfx