I don't have one, as nicknames are not really a huge thing at my place of employment,but one sticks with me, as it's a hilarious story. This is how Snowball got his name.

Snowball was a very, uh, enthusiastic Basic, with a better than thou attitude that never seemed to be brought down to a good level despite everyone's attempts. He was in Paramedic class, even though he was overall a lackluster provider at best.

One day, He was talking in the EMS room with a tech who had just brought in a violent psych. The tech was running through the call with his partner, a newer basic, on why he 'snowed' him with some versed before they even got him on the gurney.

Snowball, who you could tell had only heard this term for the first time, had a giddy smile that I still can't place. At the same time, another crew was coming in with another violent psych.

The guy on the gurney was pushing 400 pounds, covered in vomit, and had an oder that permeated the ED. He was screaming obscenities and cursing everyone he laid eyes on. Then he looked at Snowball, and began tearing him a new asshole with the amount of shit that he was complaining about. How dorky he looked, how feminine he looks, yada yada.

Anyways, after about 30 seconds of this, Snowball walks up to the guy, looks him strait in the face, and says, 'You know, if I brought you in, I would have snowballed the fuck out of you.'

For the uninitiated, Snowballing is the act of taking a cumshot in the mouth, and then making out with the person, swapping cum-laden spit from one to the other.

We burst out laughing, and Snowball turned around, looking pleased with himself, repeating what he would have done.

Thus Snowball earned his name.