The New York restaurant Katz's Delicatessan was the location for the famous scene in 'When Harry Met Sally...' in which Meg Ryan fakes an orgasm in front of Billy Crystal (and the rest of the diners).
Because of its claim to fame, there's a sign in Katz's showing which table Ryan and Crystal sat at when they filmed the scene. So what if a couple sat there and recreated it.... and not only that, what if every other woman in the restaurant joined in?
Those japesters at Improv Everywhere carried out exactly this stunt as part of their 'Movies In Real Life' series (check out their 'Rocky' one, too). Click play above to see how it went down. As it were.
(Via Laughing Squid)