TRYING not to draw attention to himself, The Count of Monte approached the empty bus shelter and reached inside his coat.

He pulled out his secret weapon, checked again to make sure he was not being watched, and placed it on the empty seat.

Glancing back at the battered paperback as he made his escape, The Count smiled to himself as he imagined who might stumble across the book and pick it up, and how far it could travel...

Using the Count as an alias, Chris Priest and his wife, Vi, from Heanor, have left about 18,000 books in public places for other people to pick up and enjoy.

They simply pop a note in the cover of each book, explaining the concept of book-crossing and requesting that, after the reader has finished, that they leave it in a public place – known as "releasing" – for someone else.

Book-crossing is a movement that has about 800,000 members worldwide, and people who pick up books are asked to log on to a website and record their thoughts about their read and the location where they released it.

Members at the start of the chain are simply asked to pick a name for themselves and register their book online.

Chris, 54, said he plucked the name The Count of Monte "out of thin air" when he started book-crossing about a year ago.

He and Vi, 36, are now aiming to smash the record for the member who has released the most books, which currently stands at about 30,000. "We really enjoy it," he said.

"My wife and I are obsessed with it – and we really do want to become number one in the world!"

Chris and Vi said they were not avid readers until they discovered book-crossing – but now the hobby has influenced their whole lifestyle.

"I wasn't really a good reader until I discovered book-crossing – in fact I was terrible," said Chris. "But I'm reading loads more books now.

"Vi picked up a book-crossing book written by two LA vegans and after reading it she became a vegan too.

"Now I do deliveries for Sound Bites in Derby, which is a vegan whole-food store and we are both following a vegan lifestyle – and that's all down to a single book that we found!"

The couple see book-crossing as a hobby and buy cheap books from charity shops for the sole purpose of releasing them. They estimate they have spent about £600 on their hobby.

Chris said: "If I played golf it would cost me maybe more than £1,500 in membership alone each year. This doesn't cost a lot in comparison and gives us a lot of pleasure, as well as giving other people pleasure too.

"We buy books in bulk from internet auction sites, charity shops and often buy unwanted library stock, too."

Checking the book-crossing website, Chris and Vi follow the progress of their releases as other people find them.

"A guy from Brazil had heard about us and e-mailed me, so I sent him some books," said Chris.

"We have heard of people taking our books on holiday, so the books are certainly travelling overseas."

One title that Chris left on a bench in Ilkeston was picked up by a woman who read it on honeymoon in New York – and left it in a hotel room there.

Another has found its way to Alabama and a third was picked up by a fisherman from Inverness.

Chris says he is now reading it while on a ship off the coast of Newfoundland. Book-crossers try to think up unusual locations to leave their books, and Chris said he had heard a rumour that one ambitious book-crosser even released his choice in the White House.

Chris and Vi prefer leaving theirs in pubs, on park benches and sometimes between tree branches.

Most often he puts them in Derby's Market Square and other busy shopping areas.

"In a pub you might read their newspaper but you can't take it away with you and it doesn't last long.

"This way you can take it away with you." said Chris.

"It is always lovely to spot someone as they find a book and I can observe them eyeing it up, almost afraid to pick it up in case there are candid cameras about.

"We have heard of plenty of people thinking it is a joke – but it's not."

"It gives me and Vi a buzz to think that there are lots of people reading stuff they wouldn't usually buy."