Found on the Baen Bar: Jeffrey Carver, author of the Starrigger series, has put his book Neptune Crossing on his website, starrigger.net, as a free download in unencrypted html, MobiPocket, eReader, rich text, and PDF formats.
The download page also announces that the other two volumes in that trilogy, Strange Attractors and The Infinite Sea, will be coming soon, leading up to his release of Sunborn, a new book in the series. He will also be doing an audiobook podcast for Sunborn.
Carver's commercially-available e-books can be found via ereads.com.
Here's hoping Carver's giveaways lead to the same sorts of success experienced by Baen and Cory Doctorow!