Javascript OS

You can do cool stuff in JavaScript, but it's definitely a horrible language to do real development in. I just ran across YouOS - an operating/windowing system that runs in your browser. I guess the idea would make me sick to my stomach, if we hadn't done something like this in my project back in 2001. It was actually a pretty neat text analytics demo using multiple iframe windows to visualize result sets differently (e.g. in a table, a graph, etc).