Books are flying off the shelves like never before, according to two of the UK's biggest second-hand book sellers.
Titles in the top 21 of the BBC's Big Read contest are most requested
Children's charity Barnardo's claims the UK is caught in a "reading frenzy", with a large rise in book sales in its shops since December last year.
Oxfam and Barnardo's say they urgently need more book donations to keep up with demand, especially for fiction.
Barnardo's suggests the change in reading habits is down to the BBC's Big Read vote on the most popular novel.
The charity claims shop managers often have as many as 10 people on a waiting list for certain titles.
John Ellis, head of retail development at Barnardo's, said: "Customers seem to be requesting those titles which made the top 20 of the BBC list, with titles like Lord of the Rings, Nineteen Eighty-Four and Pride and Prejudice in great demand."
Harry Potter books and titles by Jacqueline Wilson are in high demand among younger readers, he said.
The charity, which sells more than 1m books a year in its 300 plus UK shops, has warned it is now facing a "book drought".
"We are really pleased so many people are using Barnardo's to buy books," said Mr Ellis.
'Cannot get enough'
"However, we have almost become a victim of our own success and are now running very low on supplies."
Barnardo's has opened bookshops in Grantham, St Andrews and Aberdare, with another planned for west London.
Oxfam, which has also established several bookshops in recent years, said general fiction was in particularly short supply.
Georgia Boon, manager of the Oxfam bookshop in Reading, said: "We are actually really, really low on books for the first time in a very long time. We just cannot get enough in to sell.
"The Big Read certainly helped - all our books are categorised and it certainly helped sales of our literature section."
She said Joseph Heller's Catch-22, voted number 11 in the Big Read contest, was one of the most-requested titles, along with Sebastian Faulks' Birdsong, in 13th place on the list.
Ms Boon said: "Lord of the Rings always moves, as does Pride and Prejudice - we are selling any copies we put out. Nineteen Eighty-Four we just haven't seen.
"It's funny, when things become popular we stop getting them because people hang on to them to re-read."
She added that the quantity of second-hand books was not a problem, with business looking like it would continue to boom for some time.
"I reckon it's pretty much an infinite supply of books to be donated out there - there's always more," she said.