fast inverse kinematics

does anybody know of a good method of doing inverse kinematics in a game, i would like it to be fast enough for a game, and it doesnt have to be very precise, just basic humanoid character animation…

tutorials are fine, but i would like to implement it on my own, some some basic ideas are cool also…

thanks

follow this link: http://www.darwin3d.com/gdm1998.htm
there are two articles about IK on this page, I learn IK from that myself.

Also try this link for a more iterating approach:
http://freespace.virgin.net/hugo.elias/models/m_ik.htm