Cast your mind back to last October, and you might remember a news story about a celebrity sperm clinic called 'Fame Daddy'. In 48 hours, it had travelled the globe, being covered by over 700 news shows and channels - with #celebspermclinic even trending on Twitter.
The only problem? The story was completely fake.
It was the creation of Channel 4 comedy show 'The Anti Social Network' - a satirical take on how news is created and interrogated (or rather: not) in the chaotic culture of social media.
To find out how they pulled it off (if you'll pardon the pun) - and other great hoaxes - head over to the 4OD website to watch the show.