This is a Lisp tutorial worth reading.

This is so nice.

This release includes bug fixes, improves on generic support and introduces a few metaprogramming facilities (still on early stage).

Many thanks to the growing boo community!

What? - http://boo.codehaus.org/
Download - http://boo.codehaus.org/Download
Official irc channel - irc://irc.codehaus.org/boo

Full change log here.

Have fun!