Red Light Disco

Common in Victoria, Australia,

When you are stopped at a red traffic light to pump your music full blast and everyone gets out of the car and dances on the road until the light turns green at which point you all get back in the car and drive off

Person 1: What the hell is that guy doing?

Person 2: It's a red light disco, You see this all the time at the lights out the front of Fountain Gate