Juergen writes "You OS comes from the MIT Labs and contains an email client, Chat Function, RSS Reader, and Text Editor.
YouOS is a web operating system that lets you run diverse applications within a web browser. Small applications like sticky notes or clocks. Large applications like word processing, mp3 players, and instant messaging. Even better, it's very easy to tweak an existing application or write your own.
The first time, it's a KLUDGE! The second, a trick.
Later, it's a well-established technique!
-- Mike Broido, Intermetrics