Unreal Championship, Half-Life 2, and Quake 3 based games

I have an odd question...

Has anyone attempted to place new maps or modifications in any of these games, or games other than the Halo series? I ask, because these particular titles are very closely based on popular computer game engines, so I wonder how compatible the media might be.

I know that Unreal Championship 2 uses a VERY modified engine, so I'm not asking, the media wouldn't be able to work with UT maps, but it seems that the original UC, using very minimally modified media (If at all) would work with UT2k3 based media. At least, it would seem that way... But the file extensions seem different. If anyone knows anything about this, please let me know.

I am also wondering about Half-Life 2; as to whether anyone has attempted to input any of the mods for it onto the XBox version. I haven't investigated the format similarities yet, due to steam, this can be a large task to ascertain.

Lastly, Quake3 based games, Wolfenstein, Soldier of Fortune II, the Jedi Knight series, etc, etc. Has anyone tried to pick these apart, to add maps or content, or even to add new mods from the pc versions to them?

If there are any other games people have had any degree of success with, please let me know(aside from halo series) I am very interested in breathing some new life into these console titles, and appreciate any info greatly.