I am on the elderly side to be carrying around an iPod but I bought it to keep me from being bored on the treadmill. Then I found I liked listening to”my stuff” during long car rides or British train rides.
Just recently I have discovered that audio books are great for when you want to observe the world around yet “read.” I have to admit I would not want to listen to many types of books — things where I want my own mind to paint the picture without some narrator interfering. Yet for an autobiography read by the subject it can be great — like the recent Condi Rice book. Another book, War, which was read by the writer was, for me, best on audio. I needed to ‘hear’ it — reading a lot of the cursing & dangerous encounters from the page would not have been the same.