Last fall, I was invited by writer and Cobalt City creator Nathan Crowder to contribute to his Cobalt City Christmas anthology. I've been a fan of Crowder's series of novels surrounding superheroes and villains, as well as the related Manuel de la Vega mystery series.
Now Crowder is gone into the digital age with his books, even offering one for free! You can read his reasoning here. With more and more e-book readers becoming available, his reasoning for giving away books (try one, it's free, come on, what can it hurt?) seems sound to me. After all, it's how junkies are made.
So if you're looking for a mystery with Mexican masked vigilante and a man-panda sidekick, you can now read Greetings from Buena Rosa for free. Can't think of a better deal than that.