It's been around for quite a while; stunters use it because, for some reason, you can't get text lag in windowed mode no matter what you do, and that's important to make sure text-timed stunts like mass pppfr's go off without without a major hitch like text lag. If you don't use the -vidmode command and just use -window, the game's video settings will give you some resolutions you can set it to, up to but NOT including your desktop resolution (obviously, since it's windowed; the game won't even give you the option). And as long as there's another screen open on your desktop, you can alt+tab away from the game; it won't minimize anymore, but it switches Halo to the background, which is why you need another open window to switch to. Also worth noting, if your computer is hosting the game server, all the guests will get a serious but brief lag spike both when you alt+tab to the background and when you come back to the game. Anyway, this is definitely a worthwhile post to make sure people know about its usefulness.