My friend has a huge crush on me and I don't want to lead him on!?

The only way to ever end these kinds of things is the flat out end it. I know you dont' wanna sound like a snob / jerk, but if you don't tell him, you might be leading him on with something else that you don't know of yourself. Tell him in some kind of way, possible, preferably without the knowledge of acquantiances, maybe friends.