Where do mobsters get their nicknames?

Last week I wrote about the whimsical mobster nicknames mentioned in an article about a big Mafia boss sweep in New York and Sicily. Here's a Slate article by Daniel Engber that looks into the origins of mob nicknames, like "Tommy Sneakers," "The Greaseball," "Bobby the Jew," "Mike the Electrician," "Frankie Breeze," "Gumba," "The Indian," "The German," and "Joey the Clown."

Where do mobsters get their nicknames?
From family members, childhood friends, business associates, newspaper reporters, or the police. Not every mobster has a nickname, and some have more than one. Chicago boss Anthony Accardo, for example, was known to his colleagues as "Joe Batters." He got the name from Al Capone after he dealt out a pair of savage beatings with a baseball bat: "This kid is a real joe batters," Scarface said. But the press called Accardo "Big Tuna," after seeing a photograph of him on a sport-fishing expedition.
"Joey the Clown" Lombardo earned his nickname from the press, thanks to his fondness for zany public behavior and cheesy jokes. At the conclusion of one of his trials, Lombardo attempted to elude newspaper photographers by converting a newspaper into a makeshift mask with eye-holes and racing out of the courtroom. At a subsequent trial, Lombardo explained to reporters that a piece of his jewelry was made from "canarly stone": "You 'canarly' see it," he said.

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