While some mods actually have wide screen support, Korax at http://www.korvinkorax.com has done it again!
He’s fixed it up so the Doom3/tech4 engine supports a new widescreen aspect ratio, and sports a much smoother vsync! ~ which to me is a tech4 engine overhall in its self, as well as adding a more vibrant/in your face view of the game. Especially when the game engine its self now has the feature without needing to have a mod with its own config. We can now enjoy Doom3 at a higher res aspect ratio with Korax’s Doom3 widescreen support!
Korax’s Doom3 wide screen engine requires that your doom3/base directory resources to be intacked. ~ Basically have doom3 installed and patched, and you’re ready to extract the new executable etc, into your doom3 game folder location. And then you’re ready to enjoy the way D3 was really meant to be played, on widescreen.
More here: http://www.korvinkorax.com/2012/03/doom-3-widescreen-support/