For many late-night revelers, the temptation to hop onto a Citi Bike is too great to pass up. Michelle Young, the founder of the Web site Untapped Cities, frequently cycles from the Lower East Side to her home near Columbus Circle after a night out. After the gay pride march in June, she picked up a Citi Bike on Washington Street and “weaved through the drunk crowds” to get uptown. A cab would have cost about $10, and she estimates that she has more than recouped the bike-share membership fee by forgoing taxis and MetroCards.