Along the lines of calling my internet law class "Cyberspace Law," the courts demonstrate the origins of this archaic and downright silly terminology.
Washington v. Heckel, a case from Oregon in 2001 (2001!) refers to "unsolicited commercial e-mail." Instead of writing "spam," they refer consistently throughout the case to "UCE." Craziness.
In a related vein, I'm on a mission to drop the hyphen from "e-mail." It's unnecessary and wasteful. "Email" is universally recognized, and smoother on the typing fingers.