Mary-Kate Olsen smoking during lunch with boyfriend Nate Lowman ... Jeremy Piven hailing a cab outside Balthazar ... Robin Williams leaving his hotel ... Mad Men star Elisabeth Moss crossing the street with a Starbucks cup in hand ... Brad Pitt getting in an SUV outside the Michael Kors boutique on Prince Street and later stopping off at Mercer Kitchen ... Kim Raver, Brooke Shields, and Lindsay Price filming scenes for Lipstick Jungle ... Katie Holmes walking to a yoga class and later carrying Suri into their East Village apartment building ... and Ed Westwick walking on the Upper East Side.