If a man on the New York City subway started asking riders for money to fund the time machine he was building, you'd probably assume he was a panhandler with a particularly novel method of asking for money. But what that man's future self got on at the next stop and begged riders not to give any money, because if they do, the time machine will indeed get built and ruin all of our lives? That's the pretty neat trick Improv Everywhere pulled off on the subway, using, of course, a set of identical twins to play Current Guy and Future Guy. Three more sets of identical twins also got in on the action at other stops, playing current and future versions of other riders on the subway car.
Improv Everywhere staged the scene five times, and unlike some of its past pranks, each performance felt intimate. It "was hyper-focused on the people who happened to be sitting and standing around our playing space," the group's blog post explains. "In most performances, it felt like a surprise for just ten people. I love creating something so ridiculously elaborate (four pairs of twins, perfectly timed staggered entrances on the train) for the benefit of so few people." Of course, the video can now be enjoyed by many more people. Did the time machine builder actually get any money from unsuspecting strangers? Yes, at least $5, the blog post notes, and the giver got off before seeing how the prank played out. (Read more prank stories.)