Earlier this week I finished reading CyberStorm by Matthew Mather ($2.99 for the Kindle download). It's an apocalyptic novel in which New York gets socked in by multiple blizzards over several weeks right at the same time foreign hackers bring down the power and communications grids. I don't normally read this sort of stuff, but this one was interesting (although the characters are a bit flat, perhaps because in a "message novel" the characters aren't terribly important). It certainly gives me pause when I think about doing something like installing a wifi thermostat or wifi-enabled lighting.
