The ledges are possibly the nastiest things in Quake . They're not mutant mahogany ledges or anything, but they serve as sniping points for all the creatures in the game. There is nothing quite as annoying as walking into the middle of a pile of corpses, weapons smoking, low on health, only to have an ogre lob a grenade on you from the rafters. The sound effects are worth mentioning, too. I couldn't give a monkeys who they're done by, but they're damn good.
Monsters moan, gibbed baddies gurgle, nails clang, and it all sounds very atmospheric.
There's also a CD soundtrack, it's not exactly your usual level music, but it works. Of course, like Doom , Quake has a multi-player mode as well, which by all accounts is a stonker to play. I've heard people say that Quake is primarily a multi-player game. Quake is good, I'll give it that. But whether it's worth buying is another matter.