I thought about Podcasts but couldn't really get into them.
I happened to come upon Librivox.org--free audio books from the public domain. I can't tell you how many books I have listened to in the past year. Sinclair Lewis, Louisa May Alcott, Lucy Maude Montgomery, Mark Twain, F. Scott Fitzgerald and first-hand accounts of historical events. Surprises abound.
Many restless nights I have been lulled to sleep listening. It does take a little bit longer to finish . . . zzzzz . . . . as there is much backtracking to catch missed chapters.
Volunteers record chapters or entire books and most are quite good.
I have downloaded a stockpile of books for our trip if I have time to listen.
This is a terrific resource I highly recommend.