lmnopuz (pronounced "ell-em-en-oh-puz") is a web-based crossword game, written by me and and my friend Dan Erat.
It's still quite incomplete in a number of ways, but it's definitely to the point where it's playable and quite fun.
The source
Clone as:
git clone git://neugierig.org/lmnopuz.gitEvan Martin, martine@danga.com