It used to be, that novels were often distributed one chapter at a time.
Podiobooks.com distributes audiobooks in a similar way, using podcasts as the medium. The site features a small but growing collection of titles, most of them indie works read by their authors. After registering (it's free), just click subscribe to download chapters using your preferred podcatcher. (You can also download individual chapters directly from the site.) If you like a particular book, you can make a donation to the author, who keeps 75 percent of the proceeds.