Podcast Only is a phrase coined by Scott Sigler.
Sigler used this phrase to refer to his novels being released in podcast form rather than being released through traditional print media. AOL/Time Warner had made plans to print EarthCore as a traditional novel however, with the economic slump following the September 11, 2001 terrorist attacks, Time Warner decided to end the imprint in 2004.
Delivering novels through podcast technology began with Sigler's novel EarthCore in March 2005 and continues to this day with some his latest works being, Nocturnal and The Crypt. In addition, his success has inspired a community of writers to deliver their works directly to the listening masses. Websites such as podiobooks.com and technology such as iTunes has made it even easier to follow works of literature published in this fashion.