Why were 1,000 people dancing on the waterfront last night?

PORTLAND, Ore. -- Anyone expecting a quiet stroll along the waterfront in Portland last night was in for quite a surprise.

Why? About 1,000 people gathered for an impromptu dance party. The gathering is all the work of a couple of party-preneurs who organize these kinds of events throughout the United States.

The dance party was filled with not only people, but boom boxes. The DJ is basically someone with a backpack who has an iPod and a radio transmitter. Then everyone with a boombox tunes to the same channel. Then the dancing begins.

"There's so many people here," said dancer Sean Boyle. "It's absolutely crazy. We've been going since 8 this thing. The DDP is sweeping the nation."

The DDP Boyle referred to stands for Decentralized Dance Party, since they can go anywhere at any time. People who take part in these dance parties get the word out through social media sites like Facebook.

The DDP started in Seattle earlier this week, then came to Portland. It's headed to Los Angeles next.