Well, maybe not the best, but it comes very close to it.  For sure, it's the FUNNEST time you can have while trying to understand jQuery internal and at the same time learn about some exotic things about JavaScript and browser DOM.

What I am talking about is the More Things I Learned from the jQuery Source videos by Paul Irish.

Trust me... If you are a JavaScript / jQuery geek, it is definitely worth the time to look at them.

Paul is quite a fun guy to watch and his explanation style kind of remind me of how Head First book series are written.

Fun, Fun, Fun.

http://paulirish.com/2010/10-things-i-learned-from-the-jquery-source/

http://paulirish.com/2011/11-more-things-i-learned-from-the-jquery-source/