[defdac]

More of this. I don't know javascript that well, but looking at the annotated underscore.js was really enlightening.

[jashkenas]

If you enjoyed that, perhaps you'll dig the annotated Backbone.js as well:

http://backbonejs.org/docs/backbone.html

Interesting bits are the somewhat-flexible linked list of custom events, the proxying-through of many Underscore methods for Collections, the "inherits" helper function, and so on...