Dhewm3 Is a source port of the original Doom 3 and the AmigaOS 4.1 port is currently been developed by HunnoPPC, you can find more about the ongoing project on GitHub. Doom 3 is set in 2145 on Mars, where a military-industrial conglomerate has set up a scientific research facility to research into fields such as teleportation, biological research and advanced weapons design. However, the teleportation experiments inadvertently open a gateway to Hell, resulting in a catastrophic invasion by demons. The player, an anonymous space marine, must fight through the base and find a way to stop the demons attacking Earth. Note that while the Doom3 source code has been released under GPL, you still need to legally own the game and provide dhewm3 the game data to play.
News source: GitHub