He formed a production company called Wannabe Producers with Josh Etting through which he has produced the shows The Jamie Kennedy Experiment, Blowin' Up as well as The WB shows The Starlet and Living with Fran. Following Malibu's Most Wanted (2003), which he both wrote and starred in, Kennedy co-wrote the MTV show Blowin' Up (2006) featuring his friend Stu Stone. While working on Malibu's Most Wanted, Kennedy had ghostwriter Ellen Rapaport write a pseudo-comedic autobiography entitled, Wannabe: A Hollywood Experiment. The book chronicles his life in Hollywood as he attempts to become a star. It gives background on his life and family, and quickly dives into his adventures. It tells of such things as Kennedy's living conditions in the Hollywood slums, his beat up car, his kidney issues, and funky characters throughout the story.
He has also performed minor roles in a number of other films. Kennedy lent his voice as a celebrity in the videogame ESPN NFL 2K5 as a celebrity adversary with his own football team, the Upper Darby Cheesesteaks and he is also unlockable as a Free Agent tight end in season mode.
He hosted the Activision press conference at E3 2007, where his position as emcee was criticized for his patronizing jokes about the audience and inappropriate commentary as the new Tony Hawk game was displayed.
He often appears in movies with actor Kal Penn (Harold and Kumar Go to White Castle). In the movie, Malibu's Most Wanted, Kennedy played B-Rad and Kal Penn played an Indian who was in his group, and in Son of the Mask, Kal Penn played a friend of Kennedy's character. Kennedy also had a small, uncredited cameo in Harold and Kumar Go to White Castle, a film that starred Penn.
It was announced on June 12, 2008 that he would join the main cast of Ghost Whisperer, where he will play psychology student Eli.