Eh heh heh.
Nephilim show up in the Bible (Yep, I believe in the Bible) and if you study them a bit, they are quite mysterious.
Basically the whole concept is that when Angels came and bred with Humans (Which is why God initiated the Flood...) the result were Nephilim: Half-angel/Half-human. Now what happens when you kill such a thing? What happens to the Angel component? Angels don't really die. They are spirits, although they can materialize in human form. The theory is that the half-angel parts of the Nephilim became commonly known as demons.
Most people think of demons as the "fallen angels" that followed Satan/Lucifer, however this doesn't make sense. Demons are always trying to possess something. To obtain a body of some sort. Angels can just materialize...like that. They don't need a "host" as it were.
My theory is that the nephilim/demons are really what is behind all these paranormal creatures. Aliens (note: from research I've seen, aliens are always abducting people to figure out how to reproduce. To find a body. Maybe they have some patched-up foul body and are trying to breed a host race?) and whatnot. Ghosts: demons.
I do also believe that many "sightings" of the paranormal are, indeed, hallucinations.
Now that you are totally freaked out and think I am a complete psychopath...I'll shut up!
P.S. this was not meant to derail the thread into a "Do you believe in the Bible" debate. There's a thread for that in the debate section. If you wanna take it up, PM me and we can go there!
"Suppose we have only dreamed, or made up, all of those things—trees
himself. Suppose we have. Then all I can say is that, in that case, the made-up things seem a good deal more important than the real ones[." - Puddleglum, The Silver Chair
"I have had to believe a great deal in God because I have lost my belief in men." -Elias, Noli Me Tangere
"The price of freedom is learning to coexist with that which you hate." -- My
cousin.*rapes* I love you, Izzy.