"Anarchy rules! Flash mobs -- big, spontaneous crowds that celebrate organized chaos -- are fast growing around the world. Their mission: to have fun. Their message: There isn't one."

200 people form an instant game of Duck-Duck-Goose in San Francisco Dolores Park. Why? Because they wanted to.

All organized via weblog, email and word of mouth.

Their instructions:

-- At precisely 2:07 p.m., form giant standing circles, holding hands, on the main lawn.

-- Sit on the ground.

-- At precisely 2:09 p.m., something will happen. You will instantly know how to play along. Play until 2:17 p.m.