Recently I've been playing around with Inverse Kinematics and have been pretty impressed with the results. Naturally I want to take it further, but have no clue where to start. In particular, I would like to introduce joint limits (ie for a prismatic joint how far it can move, hinge joint what angles it has to be between, etc etc).

Currently I understand how to produce the Jacobian matrix for the various joint types. I am particularly looking for literature (preferably free, and preferably easy to understand) on various ways to implement joint limits. Also I would like to find out different ideas on how inverse kinematics can be used.