Javascript intellisense in Visual Studio

It's been a while since I played around with any serious javascript coding, but I have been seeing the improvements in Visual Studio Javascript debugging and have been pretty impressed. One of the things I really liked to see was the intellisense support for javascript. Man, if only I had that back in the days when I spent all day hacking javascript.

The question is: how does Visual studio know which libraries to display in the intellisense? The answer is to put a 'jscript reference' (my term) into your javascript file, like this:

You can get this by simply dragging the file from the solution explorer into the jscript file. It can't get any easier than that!