I have many browser windows, opened from JavaScript. And I want to manage them - place cascade, tile and resize them all at the same time. Are there any libraries that can help me?
I really don't know if JavaScript is allowed to access anything besides the window it is currently running in. Just think about the different browser implementations e.g. when a browser always opens a new Tab instead of a window (you can't resize and place them), or opens it as a child window inside the application (as Opera does) etc. Just because of that I don't think it is possible in a proper way.
If you really need a more sophisticated JavaScript Window Manager you might want to take a look at ExtJS . That gives you generally more control over your whole User Interface.
In the past I would have just used the DOM standards documentation to figure out what I can do as a starting place. www.w3.org/TR/Window/
If you are looking for a simple library that you can use, which will work well across browsers I would take a look at jquery. http://jqueryui.com/