Join a carefully orchestrated celebration of whimsy during the eighth annual social experiment meets scavenger hunt. On Fri 15, the group will release an MP3 (which you can load onto your iPod or other device) and instructions on where to meet. The next day, head to the appointed spot, press play when you’re supposed to and prepare to do something silly. Last year, participants high-fived strangers, slow-danced with items in shops and wrapped themselves in toilet paper for a mummy dance party in Bryant Park. Like we said, silly.