Windows for Warships?

Slashdot links to a disturbing and slightly sensationalistic article about the many unconventional uses of Microsoft Windows. These says everything from ATMs to warships use an embedded version of Windows and a lot of people who hate Microsoft hate this fact. But ultimately, they do have a point. Windows is overkill for many of these situations and its buggy enough that I can't help but wonder about what sort of mayhem can happen when someone hacks an ATM or worse yet, a US Navy "Smart Ship."