For a class I took a few years ago, nqueens and traveling salesmen.
Only nqueens and tsalesmen work. I do not plan on revisiting this unless I can think of a good reason to use genetic algorithms in PHP and I need my functions file again.
To run:
localhost/nqueens.php
localhost/tsalesmen.php
NOTE:
Tsalesmen takes a very long time to process. You will need to increase your maximum execution time.