I've heard of people getting away with serious academic work based on the Harry Potter series, but I think this one takes the cake. Molly Diesing is a linguist who has written on the speech-acts of spell-casting in Harry Potter. I wish I had the time to read her paper, because it sounds fascinating to a language geek like me. I'm not entirely sure I'd understand some of the technical linguistics, but that wouldn't stop me if I didn't have other time constraints that I do have.
that's an excellent article.