Sang with British pop star Robbie Williams song "Well Did You Evah?" on Williams album "Swing When You`re Winning".

Began acting in plays in high school.

Is actually credited as the Author of the yellow pages. They even went as far to put a about the author page inside the book.

Once worked at the New York Renaissance Faire (in Tuxedo, NY) and was almost fired for referring to himself as "the town Jew."

Had two guest appearances on the popular sitcom "Friends" (1994). His first appearance, as successful restaurant owner with a drug abuse problem and Phoebe`s massage client Steve, in Season One was intended to be a one-time appearance, but he returned as Steve in Season Nine, set up with Rachel by Phoebe on what was an intentionally torturous blind date, In this appearance it was revealed in the eight years in between his first appearance, Steve had lost his restaurant to his addiction, was now silk screening shirts and had developed low self-esteem due to his weight gain and recent impotence.

Hosted the MTV Movie Awards in 1995 along with Courteney Cox.

Was originally considered for the role of Marcus Burnette in Bad Boys (1995), with Dana Carvey as Mike Lowrey. Director Michael Bay today says it would have ruined their careers.

Was in love with a woman older than he when he was a teenager. His heart was broken when this woman married someone else.

Worked various jobs while pursuing an acting career. Was a waiter, worked in a clothing store, was a messenger, worked in a xerox shop, shoe store, as a hospital orderly.

Father loved opera and wished he had pursued a career in it. He encouraged Jon to pursue whatever career he wanted.

Father was a doctor.

Is the only boy of 5 children.

Is a native of Tarzana, California.

Has a twin sister.

Encouraged and was supportive with actresses Lisa Kudrow and Maeve Quinlan in pursuing acting careers.

Met Phil Hartman at the Groudlings in 1984. Suggested and encouraged "Saturday Night Live" (1975) creator Lorne Michaels to hire Hartman for the show, telling Lorne, "If you think I`m good, you should see Phil. He`s even better!" He and Phil helped each other get acting jobs through the rest of Phil`s life.

B.A. from University of California Irvine. [1979]

He appeared in the music video and sang in the choir on the song "Voices That Care."

His "Saturday Night Live" (1975) character, Master Thespian is an imitation of a professor he had at the University of California-Irvine.