Omar Sider of Arlington, Va. hired a flash mob to surprise his girlfriend, Star Morrad with his proposal for marriage in Georgetown Waterfront Park.

The flash mob is quickly organized by email, blogs, texting and social networks, and messages can be forwarded several times to increase its size. Bill Wasik, senior editor of Harper's Magazine ...

Of course, they also danced — the source says mother-of-the-bride Kathy Hilton hit the dance floor alongside Abdul for several songs, and Reum even prepared a flash mob dance for Paris (and ...