Inside the minds of internet hoaxers
24 April 2012 Last updated at 03:49 BST
When pranksters create internet hoaxes for fun - or for profit - it becomes difficult to trust what we read or see online.
Jokers and for-profit marketing companies are now devising elaborate online hoaxes, taking advantage of the in-built desire among consumers and media outlets to believe what they really know is unbelievable.
Hacking giant video monitors in New York's Times Square? Kanye West launching a web startup? Fakes like these are just about believable enough.
And yet while the medium of online video might be new, hoaxes are part of a long tradition of public fakery, as the BBC's Matt Danzico reports.