Scully asks Mulder how many times he's seen "Plan 9 from Outer Space", to which he replies "42". This is a long running geek reference from The Hitchhiker's Guide to the Galaxy as "The Answer to the Ultimate Question of Life, The Universe, and Everything." It's also Mulder's apartment number. See more
You know Scully, I was just thinking about Lazarus, Ed Wood, and those Tofurkey-eatin' zombies. How come when people come back from the dead, they always wanna hurt the living?
Well, that's because people can't really come back from the dead, Mulder. I mean, ghosts and zombies are just projections of our own repressed cannibalistic and sexual fears and desires. They are who we fear that we are at heart. Just mindless automatons who can only kill and eat.
Party pooper. Well, I got a new theory. ...