The New York Observer reports (Observer) that the late-night funnyman has signed a contract to buy another unit—this time, a penthouse—in the Art Deco-style building where he already lives, which had been listed for $9.95 million. O’Brien and his wife already have a combined-unit place, the paper reported on the building’s 17th floor, and with the penthouse immediately above it, O’Brien could theoretically turn it into a duplex. The timing of the purchase is interesting, given that O’Brien is scheduled to move to Los Angeles in 2009 to take over the hosting of the “Tonight Show” from Jay Leno.

Features in the penthouse unit include a 22-foot-long “master chamber,” a 28-foot-long “drawing room,” and twin maids’ rooms.

In other New York City real estate news, New York Knicks point guard Stephon Marbury has paid $1,374,637.50 for a 15th-floor apartment at the Hudson Condos complex on West 60th Street in Manhattan, the Observer reported. The paper speculated that the unit might have been purchased for his twin sister, Stephanie.