While it was originally reported that the jkwedding dance video (uploaded to Youtube mid July 2009) was real and not staged, it's arguable that the viral effect was manufactured by Chris Brown and Sony’s marketing and public relations people.While it was originally reported that the jkwedding dance video (uploaded to Youtube mid July 2009) was real and not staged, it's arguable that the viral effect was manufactured by Chris Brown and Sony’s marketing and public relations people.
Do you think that most cash machines are pony and trap (unless they dispense double your money requested without being asked)? 
The BouncE Streetdance Company from Sweden have recently raised the game in flash mob activity. 
A 'Bare Bones' Viral
Raygun are a UK band who (whether of their own design or not) owe a lot of their current high online profile to virals and online marketing. 
Break Out In Song is a public arts project in New York, USA that pushes the boundaries of live theatre.