Come across a story a little while ago involving the HL2 modding community. Apparently they were in the process of converting the origional Duke game and using the HL2 engine to run it. This would have been an amazing mod.
However, 3D Realms have stopped them from doing it because they are still in the process of doing this new Duke game (even though its been ongoing for the past few years). I think they may be afraid that if the mod is done to completion then the new Duke game would suffer lack of interest.
Wonder if the new Duke game is actually going to be released shortly with this kind of reaction coming from 3D Realms.
It would be great seeing some of the old DOS games converted by the modding community to run on great game engines like HL2.
Link to story :
http://www.pczone.co.uk/news/news_story.php?id=114208