As Take That continue to cause pandemonium on their current 'Progress Tour', it's clear that some fans live and breath their favourite music stars.
So in our latest feature we thought it was time to pay tribute to some of the most devout, obsessed, crazy and dedicated fans in the world - from Lady Gaga's 'Little Monsters' to My Chemical Romance's band of Killjoys.
You'll also see fans of Cheryl Cole, Jessie J, Nicole Scherzinger, Liam Gallagher and The Beatles and Jackson – whose fan base seems to have got even bigger since his death in 2009.
Can you think of any other suggestions? Post your thoughts in the comment form below – if you're logged into Facebook you can comment straight away.
Big star - without their famous masks
Muse bring robots, fire, David Cameron and their own currency to Ricoh Arena
R&B star seen in big hair and tight jeans in NYC
Who's done what for the charity event?
Mark Owen wants to see his band play the festival