They were once the preserve of those with failing eyesight or long-distance drivers with hours to while away.
Now audiobooks are experiencing a popularity boom linked to the rise of smartphones and credited to increasingly hectic lives on the move.
Scots publishers are among those reporting a rise in demand and are searching for leading film and television actors to narrate their novels.
With boxes full of cassettes and CDs a thing of the past, downloadable files are now a preferred format on the train, bus and tube.
Audible, the sole supplier to iTunes and Amazon, expects to see a 30 per cent rise in business from this Christmas compared to last, and has been growing at about 40 per cent year on year overall.
Canongate, the Edinburgh publisher, said it has revisited audiobooks in recent years and is using actors such as Dominic West and Benedict Cumberbatch to narrate its titles.
Some individual authors are even seeing greater demand for audiobooks which are, increasingly, no longer viewed as optional extras to physical copies.
Ian Rankin and Robert Galbraith – the pen name of JK Rowling – have dominated the Audible charts in recent months, while emerging authors such as TF Muir, whose St Andrews-set crime thrillers have been a hit both at home and in the United States, are selling more audiobooks than physical copies.
Laurence Howell, director of content at Audible, said that the barriers to enjoying audiobooks have been removed with new technologies.
“If you look at audiobooks, 15 years ago it was a closed world, hidden away in the basement of book stores,” he said.
“They were very expensive, abridged, so the reader wasn’t getting the full text, and usually came in a large box of four tapes or three CDs.
“And when you wanted to listen to them, you would go home and sit and listen or listen when driving – the experience was very static.
“Now our members can very easily download any one of 100,000 books on to almost any device and listen to the full unabridged work on the go.”
He said that smartphones and other devices have changed the nature of the industry, and listeners now get through stories on their morning commute or during their lunchbreak. He said: “People’s lives have changed. You always hear people say, ‘I wish I had time to read more books’ and now they can. The way we think of it is their eyes are busy but their ears are free.”
Key to the growth is good narration, publishers say. Hollywood actors including Anne Hathaway and Colin Firth have narrated one-offs, while Alan Cumming recently read Macbeth. Barack Obama famously narrated his own best-selling autobiographies and Glasgow crime author William McIlvanney recently recorded his original Laidlaw novel.
Mr Howell went on: “There are now instances where audio downloads outsell physical copies.
“One example is JK Rowling writing as Robert Galbraith. We gave it a good push, it got fantastic reviews and it sold 4,000 downloads, far more than book sales.
“Glasgow author TF Muir is another. He’s fairly new but has released four books and certainly at one stage they were outperforming physical sales.”
Muir, 63, a civil engineer from Lenzie, East Dunbartonshire, said he had little prior knowledge of the audiobook industry but that it has helped sales both in the UK and in the US.