Chrome in desktop format. Extremely low power use, durable, small form factor, and managed in the cloud.
What is ChromeOS?
ChromeOS is a web-based operating system designed by Google. It is designed to work primarily with web applications and does so through the Chrome browser and it’s extensions. There are a few native applications outside of the browser(file manager, media player, calculator), but for the most part the operating system is very basic. Keeping things simple and on the web allows ChromeOS to run on lower cost hardware without taking a performance hit.
More info on ChromeOS
Buy the latest version here for $260.