Also interesting and worthy of note is that this project transitioned to BSD recently, and they are doing it as part of a donation drive.

http://www.shenlanguage.org/shenbsd.htm

I am an amateur Lisper, and like others I whined (perhaps irrationally) that their custom non-OSI only one implementation of the language or else license was scaring people off. Not that the BSD license assuages my concerns about community weirdness (hard to describe, but this ia a very personal opinion and you can dismiss it), but I would like to see if the demand will drive open sourcing the code.

Also very cool is that you can find Shen implementations in more than one flavor: Common Lisp, Clojure, Ruby, and more. Definitely check out the site if you have not yet.