Oops, he did it again. John Mayer put on a show for the paparazzi in NYC on Nov. 27 when he leaped on top of a car hood. "He started acting like a monkey and screamed 'Happy Thanksgiving,'" describes an onlooker.

John, 31, has gotten in trouble for playing to the cameras before. In August, he spilled his guts to a crowd of reporters about his breakup with Jennifer Aniston, 39. Afterwards, an agitated Jen said, "Trust me, you'll never see that happen again from that man."

What on earth is going on with John and Jen? For the latest on their relationship, pick up the new issue of Life & Style, on newsstands now!

Photo Credit: Celebrity Photo; WireImage