New York celebrated its 40th anniversary on Friday at the Hammerstein Ballroom with performances by The National and Grizzly Bear. We asked several guests how they celebrated milestone birthdays (Katrina Bowden just turned 20 at at the Soho Grand), but were terrified by Michael Ian Black's birthday wishes: "I want to get some ass play. Interpret that how you will." Yipes! Get more birthday plans by viewing our Party Lines slideshow.