Macchina magnifica

The Machina Magnifica was a doomsday machine designed and owned by Leonardo da Vinci, and constructed with help from Philip J. Fry who was led to believe it was an ice cream machine (ice cream is only a byproduct of use). The machine was used to attack those on Planet Vinci who had made Leonardo and Professor Hubert J. Farnsworth feel inferior, but it was stopped and presumably ruined by Fry before it killed too many.

Trivia

 * Though its primary purpose is to exterminate everyone who ever made its inventor feel inferior, its byproduct is ice cream.
 * Machina Magnifica translates to Magnificent Machine in Latin, and, with a minor change in spelling, Italian.