In elementary school, I was known for being a "human dictionary." Funny thing is, I learned a lot of words from games.
At my volunteer job, we get free food (often pizza). However, because I don't want to get into a habit of fattening myself with greasy pizza (I eat a lot as it is), I bring my own food. This has given me a rather amusing reputation, as one girl constantly asks me what I've brought for lunch.
In martial arts, I'm known as "The guy who doesn't tap," as well as "The guy with the 90 degree spine." Since I've cut weight, I've became a skinny bastard (still working on building muscle), with bony shoulders, giving me the awkward nickname of "Boner" (although thankfully it's only been said once)
And among my friends, I'm known as the guy who is awesome at gaming. And of course, the crazy health/fitness/martial arts obsessed zealot.