[Javascript] Looking for a JavaScript version of a phpInfo type page

[Judah Frangipane]

I'm looking for a JavaScript version of a phpInfo() page. In php you 
have a method called phpInfo(). This method gathers as much information 
as it can about the server running php. I need a JavaScript script or 
method that will grab as much information about the client as we can get 
so we can have them send it back to us. Stuff like, OS, browser, 
version, etc.

Thanks,
Judah