I have just read through 92 pages of this epicness. No regrets, haha.
[spoiler]Rachel: Who are you to play games with us? Who are you? What are you?
Ellimist: *shows her his life*
Rachel: Oh...well, answer this, Ellimist. You're clairvoyant, right? Like, you can see the past, present, and future all at the same time?
Ellimist: Oh, yeah!
Rachel: ...can you tell me how Lost ends?
Ellimist: Rachel... there are some questions that even I can't answer.
Rachel: Yeah, okay then. Okay then. [/spoiler]
Well...it may not be the funniest, but the person who knows where this quote originally came from is awesome =D