With liveBook:

- The books are free

- Full-text search for books

- Browser-based

- Audio readings with an arrow on the left / text highlighting to keep up with the book

- On the right-sidebar of a book, it offers to buy the book in PDF/ePub/kindle form.

This is similar to Leanpub's online reading option (https://leanpub.com).

I used it to write and publish The Tao of tmux and made it available online free (https://leanpub.com/the-tao-of-tmux/read). Like liveBook, users can opt to buy the book in DRM-free epub/pdf/mobi and have it sent to their Kindle.

What liveLeak seems to have that Leanpub doesn't is audio readings.

Another cool trick: on the left side of a liveBook (e.g. https://livebook.manning.com/#!/book/grokking-algorithms/cha...) mouse-over on the left side of a section of the book and you can start narration at that point.

Thanks!