I listen to a lot of audio books. I'm not sure whether their popularity is equal in all countries, but in Sweden more and more people seem to enjoy them, and they are also popular at the libraries. Back in the 90's, I used to listen while I did something else, for example in the kitchen. Later, when I got problems with my neck and had to spend a lot of time just lying flat on my back, the alternative to listen to books, without having to hold them and turn the pages, became even more valuable to me, and it still is.
I love a good "bedtime story", and audio books have taken me through many a night when I have had trouble sleeping because of pain problems. If I fall asleep while listening, that's just good. And if I can't sleep, at least I get something else than my own problems to think about! I listen to CD's or tapes, or MP3 with a timer, so that they turn themselves off after 30-60 minutes. At night, I usually prefer to listen to a good book I already know, so that I don't have to concentrate too hard. With audio books, it is not only the content of the book that is important, though, but also that you like the voice.
Those of you who sometimes read my margin or my weekly quotations won't be surprised that some of my bedtime favourites are children's books like Winnie-the-Pooh, the Chronicles of Narnia or Harry Potter. Other books/tapes that I have listened to more times than I've ever bothered to count are Three Men in a Boat by J.K. Jerome, and some stories by P.G. Wodehouse. (I do have a strong preference for British English...) Recently, I've been re-listening to some Swedish classics by authors like August Strindberg and Hjalmar Bergman (late 19th - early 20th c) which I have on tape.
Quite recently, I found this website: Free Classic Audio Books, where you can download some free classics as either MP3 or MB4 for iPod. Good place to start if you can't afford to buy, or just want to try out what it feels like to listen to a book, if you're not already used to this way of reading. Enjoy! :)