Thanks to xamadeix for the heads up!
A demo has now been released for Monolith's other big game from 2005, the survival horror themed Condemned: Criminal Origins. Originally released on the X-Box 360 late in 2005, it is now being released for the PC on April 11th. The game uses the F.E.A.R. engine, and it also employs a first person perspective. The game emphasizes melee combat over run and gun, and particularly puzzle solving. The demo is 455 mb, and offers one level of the game where you must begin piecing together a rather nasty murder and also follow a suspect through a destroyed building.