I'm "Grapie" because there are multiple Katie's, but it didn't really stick.
We have a Lobo (Laura) because I got lazy.

We have Itchy, for no reason other than a senior needed to get his attention and just said names till he turned around, and Itchy worked.
Yoda was a self-proclaimed name, but I met him as Yoda, so it stuck.
J-hawk: One of our teachers has a long name that doesn't follow the rules of pronunciation, so we just call him Mr. J, J-Dog, J-Dizzzle, etc... J-Hawk is our favorite (often followed by a loud "PCAW" from someone in the vacinity)
"The Twins" was given to two freshmen girls because they were almost always together at the beginning of the season (they don't look anything alike)(at all)
And Slurpy, because as a Freshman, he had newly aquired a retainer and slurped.... ALL THE TIME.
We take pride in the names we give.
I also have nicknames for everyone:
Janedawg (Janelle)
Jackson-bear (Jackson)
Kev-Bev (Kevin Kolo-J)
SarSar (Sarah)(Which also stuck on the entire team)