A feel-good Twitter request by the New York Police Department asking for pictures of people posing with officers quickly turned ugly when hundreds instead posted shots of baton-wielding cops battling protesters and taking down suspects. Other recent examples of Twitter gaffes:

— JP MORGAN CHASE: Fresh off a multibillion-dollar settlement stemming from the financial crisis, the investment giant launched the hashtag #AskJPM for people to ask career advice questions. Among the unanticipated responses: “Did you have a specific number of people’s lives you needed to ruin before you considered your business model a success?” and “Did you always want to be part of a vast, corrupt criminal enterprise or did you ‘break bad’?”