Stacks of precariously piled books are popping up in weird and wonderful locations around the world.
Towers of tomes have been found in front of the Sydney Harbour Bridge, in an empty lift, on the Brooklyn Bridge, and on a child's swing.
They are the work of one man, who emptied his apartment of books in an attempt to get people off screens and into books, creating a new kind of social network along the way.
Shaheryar Malik, a New York-based art director originally from London, came up with the idea a year ago when he was walking over the Brooklyn Bridge and got the urge to take a selfie.
Instead of taking a photo that millions of others had snapped, he decided to share something else with the world.
He left 40 books in the public space and walked away.
Part-commentary on the way we live today and part-experiment, the books contained a simple note encouraging passers-by to take a book for free, read it and then email their thoughts to Malik.
"The books I left on Brooklyn Bridge were all mine I have read already," he told SBS.
"I select the books so that there is a wide range for people to pick from - comedy, self-help, biographies, fiction, graphic novels, and much more. Titles have included The Decision Book, The Buddha Walks Into A Bar, The War of Art, The Alchemist, The Rise and Fall of the Third Reich and Shit Happens So Get Over It."
His primary aim was to just get people to read one book.
"I know how difficult it is to even get through one book but the aim is to get people to read one book," he says.
"Then hopefully that would trigger them to be on the look out for other books or spark a subject that they want to know more about.
"Reading has to be a conscious decision, so to me, choosing not to read is like 'choosing to go blind'. Why would you do that?"
By asking readers to email him with their reactions to the book, he hopes to not just inspire people to read more, but to think more too.
"I'm pretty amazed with the response," he says.
"I don't really communicate with them as that for me could loose the appeal of the idea. For me it's better if there are some unanswered questions on both ends. People generally love the idea and coming across the stack and then reading the book."
So far Malik has left stacks of books in New York, London and Sydney, and he plans to expand into other cities and countries in the future. He has already received emails from people from more than 30 countries.
Since offloading all of his own books, Malik has left books donated by friends and family too. And says he has found the experience uplifting.
"I have given away something, but I've never really left them," Malik says.
"What you've read becomes you and stays in you, and now they carry on and get extra lives."