The Register reports that the US Army has abandoned Windows and chosen Linux for a key component of its "Land Warrior" programme...

http://www.theregister.co.uk/content/54/33611.html

For those who don't know the Land Warrior Sytem is the Army's new infantry solders personal body armor. It has or will have an integrated set of medical sensors, tactical radio, GPS, night vision, infrared camera, off shoulder sighting system and heads up display in the helmet.

The big problem was OS stability battery life/rechanging and battlefield integration with a command and controle source.

It looks like all thats left now are the hardware problems.

Hmm.. infantry's personal body armor.. Now, all we need is to shape the armor like a penguin and I can imagine an army of Tux's invading the world.. MUAHAHAHAHAHAHA