cl-skip-list
cl-skip-lisp is a lock-free skip list implementation that works with SBCL 1.0.42 and above. Its source can be found here: http://github.com/kraison/cl-skip-list.

Author: Kevin Raison

License: MIT

Homepage: http://github.com/kraison/cl-skip-list

ASDF-install package (obsolete) http://chatsubo.net/~raison/cl-skip-list-0.3.tar.gz