Have you guys heard of this? It's a very promising (still WIP) non-commercial project aimed at remaking the original Duke Nukem 3D in high-quality true 3D, using the Unreal Engine 3. This project has been officially sanctioned by the current copyright holders of the Duke Nukem franchise, and it is going to be a freeware stand-alone game. The primary objective of the development team for now is to recreate the original episodes of Duke Nukem 3D with both single- and multiplayer capability. A multiplayer-only beta demo is expected to be released in the near future.
Duke Nukem 3D: Reloaded Official Website
Duke Nukem 3D: Reloaded Official FAQ
Duke Nukem 3D: Reloaded Developers' Blog at the Official Forums
Duke Nukem 3D: Reloaded Wikipedia article
Duke Nukem 3D: Reloaded at ModDB