ZCast - Live interactive podcasting with your Twitter followers
ReadBit - Read wisely & save time with text-to-speech audiobook reader
Overcast - Video-first asset management for teams
Listening.io - Turn articles into audio and listen in your podcast app
Audioread (formerly Audiblogs) - Audiblogs lets you listen to any web article in your podcast player in an Audible-like voice.
article2audio - The next generation of text-to-speech focused on web content. It understands and enhances English articles and blog posts beyond just words.