This is very clever and deserves a lot of points. It doesn't look very interesting on the landing page but once you get into it, it's well written and there are some clever strategies (including a small JavaScript console at the bottom you can use to test bits of code while learning).<p>I haven't got the time now, but I'm going to work my way right through this one day - what I looked through seemed very solid.<p>The only downside? The font chosen for the code examples looks pretty gross on OS X, but since you can download the book as a ZIP file, it can be changed in the stylesheet! (I'm hoping..)