I still remember the very first time I saw this. Me and a kid I knew were big into our PCs, so when he got a new GPU I went around to see it. He was playing Half Life, and was shooting some dude in the ass who was hanging from a lift. I was cracking up.
Went out and bought it a couple of days later. Got myself a Voodoo 2 and happy days. One of the finest games ever made. Super complex, character interactions were just incredible and the graphics were amazing too.
And it worked, and it was pretty much bug free apart from a couple of annoying levels with a crusher where you would just die for no reason.