For everyone who doesn’t yet know how the IKs work in Blender here are few ways to do it. Basic IK and some special tricks also…
http://members.lycos.co.uk/kurppa/ik.html
It’s my first tutorial so comments would be nice… is it just a load of nonsense crap or actually something useful?
Hehe… great,
but working on my spider, at the 5th IK chain (5 added armatures over a main armature to make tube movement… do you remember 
) blender becomes incredibly slow…
Stefano
S68: you can adjust the number of iteration for the IK calculation in the Constraint window. A lower number of iteration is faster but less precise.
Martin