Been out of touch for a little while, I've missed CGTalk like crazy!
These days I've been really interested in FBIK, but it seems like there are a lot of technical issues that keep us puzzled.
I've released and FBIK rig including simple geometry under the creative commons license. Totally free to use and modify as long as you respect the license. The feet are connected to a floor contact plane so the steps are really natural, and it should be great making a walk cycle. The usual problem with the toe is fixed, after I found an obscure passage in the documentation that said the toe should be labelled as an extra finger instead of a thumb!
Anyway, comments, feedback and input are well appreciated!
here is the link: http://www.artsy.ca/archives/182