International Pillow Fight Day

From International Pillow Fight Day Website:

The event is held in early April which is now considered International Pillow Fight Day and squares and parks across New York quickly become covered in feathers. It starts in the afternoon and lasts for a couple of hours until the participants are worn out. Aside from the great fun it also is a charitable event because the pillows can be donated to local homeless shelters. So grab a pillow and join the blowout.