It seems pretty far fetched, but Audiobooker reports that as part of Amazon’s push of their new “Whispersync for Voice” feature for Kindle and Audible that it has made $500 of audiobooks free. I’ve tried it, it does work, though I had to finally connect my Audible account with my Amazon account. The 26 titles are classics, including Frankenstein, The Wizard of Oz, Gulliver’s Travels, Bram Stoker’s Dracula, etc. read by professional narrators like Simon Vance, Alan Cumming, Jim Dale, and more.
Update: There’s also a significant discount for buying the audiobook for other Kindle books. Some titles include free ebooks like Four-Day Planet and The Cosmic Computer by H. Beam Piper ($9.95 sale price audiobook) and A Princess of Mars by Burroughs ($1.49 sale price audiobook), as well as discounts on non-free ebooks such as A Discovery of Witches by Deborah Harkness or The Hunger Games trilogy, the Hugo and Nebula winning Among Others, Jim Butcher’s Storm Front, American Gods, Michael J. Sullivan’s Riyria Revelations, The Kingkiller Chronicles by Patrick Rothfuss, Ready Player One, The Night Circus, Kevin Hearne’s Iron Druid Chronicles, Foundation by Isaac Asimov, … For the complete list of Whispersync-ready titles, you’ll have to brose 750 pages of 20 items, though the sf/fantasy section “only” lists 1500 titles.