I've been working on extending my d3.js knowledge again - this time getting a more deep understanding of how it works and what it does. I've had a good deal of help in the form of two books, one a Christmas present from my family (Interactive Data Visualization for the Web - highly recommended) and the other a book I got in one of the online sales (Data Visualization with D3.js Cookbook - a Packt book so it suffers the usual "could really need a proper editing"-symptoms).
Anyway, it's seriously great fun to play with d3.js - it's a great library and very easy to use. The Interactive Data Visualization book makes it a breeze to pick up - I'm pretty much through the book by now and all the examples work really well, especially if you have your laptop on your for testing (though, remarkably, you'll get most of the stuff even if you can't test it at the same time).
But, the point: while going through the learning motions, I've done some examples on various d3.js techniques/features. They're here:
The source for each of them come in under 150 lines of js - that includes spacing for proper reading and such, which just underlines how easy it is to get things going. Anyway, I might write more about the library as it is truly awesome and great fun to play with.