LibriVox - free public domain audiobooks
Angel's Vox - Angel’s Vox is the first audio player on the market designed specially for audiobook enthusiasts.
OverDrive Media Console - Download eBooks and audiobooks from your library directly to your iPhone, iPad, and iPod Touch!
BookDroid - BookDroid is an audio book listener for Android devices.
Listen Audiobook Player - Feature rich and easy to use player for your audio books.
Blogcast - Turn your articles into audio