Inverse Kinematics

I’m interested in learning more about inverse kinematics. Does anyone know of any good online resources for studying the topic and the underlying mathematics that are involved?

Something I found via google:

...I am wondering why you are having a problem? I mean, I found a ton of links googling "inverse kinematics tutorial"; have you done the same? Is the issue that you can't decide which is best? Perhaps you should look at as many as possible, and form your own ideas. I agree that it isn't easy; I only understand the bare basics of it myself (if that).

It's not an easy topic! :)