Deathray Games released one of their games under the creative commons license.

It is a very simplistic, one-player, fantasy hack’n’slash browser game which leaves a lot to do with it.

You can easy adopt it to have it build in other game engines, make it multi player whatever as long you follow the creative commons license.

Game: http://deathraygames.com/play-online/drg/greenhydra/index.html

Download: http://deathraygames.com/play-online/drg/greenhydra/archives/LOGH_v1.zip

Deathray the developer of this game joined CE and will answer any questions you have regarding the script/game/license.

Forum: http://criminalexistence.com/ceforums/index.php?board=772.0