I like the feeling after I know I've got enough notes but the revision is bad (purely because it's on subjects I don't enjoy) but if it was on the English I'm hoping to study I wouldn't be able to put a book down.
Saying that I did enjoy coming across a site about Amazonian cannibals after trying to find proof that they existed for an essay. I'm also enjoying reading about my chosen 3k word essay subject.
Oh, and the feeling you get when you finally whack out the last sentence in the essay conclusion. A big sigh of relief and a big weight lifted off your chest.