GoodBooks.io - Largest curated collection of 8,500+ book recommendations.
Audible - Audible is the world’s largest provider of premium audiobooks and spoken word content.
BookAuthority - BookAuthority collects the most recommended books on business, technology and science - as featured on CNN, Inc and Forbes
Downpour.com - Listen to high quality audiobooks instantly. Download audiobooks to your iPhone, Android, or other listening device. Find titles including best-sellers and new releases. Downpour, where content reigns.
Goodreads - See what your friends are reading.
LearnOutLoud.com - LearnOutLoud.com is the web's largest resource for audio & video learning.