The part at about 0:58 in the Half-Life trailer could have been a lot cooler... I picture it something like this:
CAMERA - shot is of a darkened hallway, with a blurry figure in the foreground, half in shadow and half bathed in red emergency lighting. At the far end of the hallway a zombie, in silhouette, shuffles past from right to left. The camera then clumsily focuses on the blurred figure which reveals a headshot of GORDON FREEMAN, looking down at the floor. He slowly raises his head, and then his arm pops up into the frame, clutching a crowbar that is dripping some sort of fluid...
Still a good clip though!
[edits for typos and clarity]
This comment was edited on Sep 10, 01:26.