Yeah, a couple of times if I recall. Everyone almost always goes through it at least once. Disappearing and then reappearing with no memory of this place. Once in a great while someone remembers. Nope, it's all very random and it doesn't work on any kind of system or it isn't anything.. that has to do with aliens.
Mmhm, let's see. There's the Tenth, his human clone version. The Fourth. The Eighth.. I think thats it.