If you're a fan of audiobooks for roadtrips, workouts, or commuting, check out http://www.audiobooksync.com/. This website is going to be providing two free audiobooks every week this summer, starting today.
One of the two books each week will be a young adult title and the other will be a classic, "summer reading assignment" type book that share a common theme. This week's pair is The Eleventh Plague by Jeff Hirsch and The Grapes of Wrath by John Steinbeck.
These titles are only available until June 21, when they'll be replaced by a new pair. Once you've downloaded the MP3s, however, you can wait and listen to them whenever you like (they don't expire).