The Kindle versions of Substrate Wars books are on sale until Friday — FREE for Red Queen, $0.99 for Nemo’s World, and $2.99 for the just-released Shrivers. Similar bargains are available in some non-US Amazon sites.

Too bad I can’t offer a similar discount on the trade paperbacks, but the bundle of three makes a good gift for your STEM graduate friends or relatives who like thrillers with heroic scientists — c. 1000 pages of fun reading.