God bless South West Trains. Not a phrase you'll often hear in London's leafier southern suburbs – but without one of their seasonal delays in service last week, I wouldn't have stumbled into the waiting room at Wimbledon Station and discovered, joy of joys, the Station Bookswap.

It was the poster pinned to the door that pulled me in. "Never be bored on a train journey again!" And there, propped up on the window sills, a smattering of books, their covers tantalisingly open to view. The selection ranged from a mint copy of Nick Hornby's A Long Way Down, through some battered Jodi Picoult and James Patterson hardbacks to a decent Penguin Classic edition of Dostoevsky's The Brothers Karamazov, all bearing the fingerprints of Wimbledon readers.

And it's true what they say. Books really do furnish a (waiting) room. The formerly dank and draughty surroundings of Platform Five seemed instantly less prosaic. Most colourful of all were the children's picture books, not just Spot at Christmas but bilingual texts in Hindi, Tamil and Chinese.

Some reading around reveals the man behind the scheme: twenty-nine-year-old Anthony Fairclough, legal researcher and chair of Merton Liberal Democrats, who does the Wimbledon to Waterloo commute every morning at 7am. Finding the cut-and-paste PR of the Metro newspaper barely lasted him two stops to Clapham Junction, Fairclough set up the book-swap last November.

The rules are simple. Take away a book, any book, to read at your leisure and return it once you're done for another. The idea actually originated further down the line at Raynes Park, where a swap has been running since the local library refurbished and wanted to offload some stock in 2005. To date, commuters have picked up 22,000 titles and rumour has it they're swapping at Morden Tube now, too, making Merton London's most borrower-friendly borough.

Anything goes, says Fairclough, from cookery books to out-of-date legal textbooks. His last find was an old 80s anthology entitled Sixty Tales of the Supernatural – like a book club, the swap gets you reading things you might not pick out in a shop. It certainly brings new meaning to the term "travelling library", a bit like those dog-eared copies of Alex Garland's The Beach that do the rounds of the South East Asian backpacking circuit. Except these books are on a return ticket.

At least, that's the idea. As yet, they rarely make it back to base. The book-swap is getting through 100 volumes a week, and while local libraries and Wimbledon's Freecycle network help Fairclough keep up with supply, he is exploring other ways to encourage returns, from printing up stickers to tapping into BookCrossing, which allows you to register titles and track them from person to person across the world.

Buoyed by his community spirit, I drop off a bag o' books on my way into London, including one of the four One Hundred Years of Solitudes our house has somehow accumulated. Hanging around for as long as I can without risking arrest under the Prevention of Terrorism Act, I keep watch on the waiting room. No one goes in or out.

And yet, returning the same evening, Gabriel García Márquez has gone. It's a thrill, imagining his onward journey. (As blogger Cover Girl has discovered, reading on public transport can be quite the ticket to romance.) Is it too much to hope that one day there could be a swap in every waiting room of every station of every town in the country? Would you use them? And what books do you recommend for the daily commute? Anything has to beat Metro, after all.

