LibriVox - free public domain audiobooks
Hoopla Digital - Audio books, movies, music, and ETC. Very similar to libby.
Audible - Audible is the world’s largest provider of premium audiobooks and spoken word content.
OverDRIVE - Make workspaces and sites automatically from Google Drive
DigitalBook.io - Free audio books and eBooks. Search, browse, listen, read and download over 100,000 free audio books and eBooks.
Kanopy - Kanopy is a stunning solution that makes it easy to find and stream meaningful movies.