Trunk Monkey is a concept originally created in January, 2000 by Sean Sosik-Hamor for the automotive group of Subaru enthusiasts in the New England Subaru Impreza Club, or NESIC. The original concept of a "Trunk Monkey" was a small stuffed animal placed in the trunk of a vehicle which came alive and jumped from side to side to help distribute weight during "spirited driving maneuvers".

The Trunk Monkey television ads, loosely based on this concept, were created in 2003 by the advertising agency R\West in Portland, Oregon. Originally created for the Suburban Auto Group of Sandy, Oregon, the spots have also been syndicated to multiple dealerships across the country.