Been playing with the gravity gun mod for doom 3, pretty fun, for ragdolls doom is easily on the same level as hl2, not as many physics objects though. I made a little marine stack.
[img]http://homepage.ntlworld.com/gerald.marley/Doom/pileup1.gif[/img]
[img]http://homepage.ntlworld.com/gerald.marley/Doom/pileup.gif[/img]
Marines get lonely on mars with no women loney:
http://homepage.ntlworld.com/gerald.mar ... dangle.jpg
More or less proves that a gravity gun of some type was in the game at one point, and id weren't bullshitting about it.
Can dload that mod here
http://files.ingame.de/doom/mods/gravmod.zip reading the readme is advised to get it working (for once).