Boen was also very active in the voiceover field, voicing characters such as Horace Bleakman in the Clifford the Big Red Dog television series, Police Chief Kanifky in Bonkers, the narrator and King Terenas Menethil II in World of Warcraft, Señor Senior, Senior in Kim Possible and LeChuck in the Monkey Island video game series.

Boen appeared (alongside Tom Jones) in an episode of The Fresh Prince of Bel-Air in 1993 as a Princeton admissions agent.

Other films in which he appeared include The Main Event (1979), Battle Beyond the Stars (1980), 9 to 5 (1980), Soggy Bottom, U.S.A. (1981), The Man with Two Brains (1983), To Be or Not to Be (1983), Alien Nation (1988), Marked for Death (1990), Naked Gun 33+1⁄3: The Final Insult (1994), and Nutty Professor II: The Klumps (2000).

He voiced the villainous pirate LeChuck from the Monkey Island series of adventure games.

Boen retired from screen acting in 2003, but continued his work as a voice actor in radio, television cartoons and video games until 2017.