It's not yet completely finished, but if you have Dark Forces lying around (or just bought the Steam release) and want to make it a smoother, less pixellated and have mouse-look enabled, check out the latest build of the project that renders the game using OpenGL in a brand-new custom coded engine:
Accelerated Dark Forces Extended
Works a treat on my Vista setup, but I had to copy the game directory from the Steam default to a C:DARK directory.
Brilliant! Also if you want more Enhanced Dark Forces experiences, there's a Dark Forces mod for Jedi Academy here that recreates the first 6 levels.