(applaud's Misanthrope's rather predictably sticking to his, quite overtly defined, character)
My best friend bought be a complete set of really cheapass garage-sale bought golf clubs and bag once when we were starting to get into playing golf. They were nothing great or anything, but I didn't have any golf clubs - and then suddenly I did. It was very cool.
Another time, the first time I got REALLY drunk (New Year's 2000), he basically babysat me while I puked my guts out and then worked my shift for me the next day (on no sleep), and saved my relationships with a couple of people by explaining all the stupid shit I said/did, and saved my job.
Another of my best friends once arranged to drive me up to a Halloween party in a Hummer, and then arranged for me to an all-inclusive stay in one of the rooms upstairs (a bed and breakfast), and drove me home the next day. That was very cool as well.
Another of my best friends once wrote me a story - his re-interpretation of the Bible, strictly for my amusement. It was, like, 10 or 12 pages long or something (I don't think he got past Genesis) it was great.