RGB Classic Games Forum

Return of the Triad is a fan recreation of Apogee' FPS classic, Rise of the Triad that runs on the Doom engine (more accurately, the ZDoom port). It uses the original resources (graphics, sounds and music), and tries to keep close to the original game while utilizing the features of more advanced engine to the game's advantage. The current release, v1.5, has 11 single-player levels which are completely new, and 6 multiplayer maps.

Return of the Triad Home Site (has download links)
Return of the Triad at ModDB
Return of the Triad gameplay video

This is incredibly awesome.