That's what author Scott Sigler did with his new novel Infected. Originally a podiobook (podcast audiobook) given away for free, Infected is the sort of novel no publisher in world would think would sell. It tells the story of Perry Dawsey, an ex-football hero who develops a strange malady: odd, blue triangles start appearing all over his body. But Sigler's twist is that the infectious agent is sentient. Perry attempts to rid himself of his malady in the horrific episodes that follow, all while it burrows deeper into his own psyche.

With a premise like this -- and given the, erm, nature of some of the scenes -- traditional publishers were doubtful. But Sigler's podiobook amassed a huge online following with millions of downloads. On his own, with no marketing campaign other than word of mouth and his blog, Sigler built the sort of rabid fanbase authors -- and publishers -- dream about.

And eventually a traditional publisher, Crown Books, took notice and was savvy enough to publish it -- all while allowing Sigler to continue giving away the free podiobook and provide a free PDF download of the entire book. Give it away AND sell it? Seems crazy, right? But the bet paid off: INFECTED sold 3,500 copies in the first week, more than three of the books on the hardcover fiction NY Times Bestseller list. It has sold 1,000 copies a week since. The publisher is ecstatic with the result.