Ask HN: Getting Dangerous with Javascript?

Start by implementing yourself a complex javascript widget. Like, say, a datepicker. That's a reasonable complex widget. Or start smaller with a dialog. Then, start going through it finding ways to optimize, rinse and repeat.

There was an HN post addressing your question not so long ago:

http://news.ycombinator.com/item?id=2016334

From the documentation where you can find plenty of docs and tutorials: http://docs.jquery.com/Main_Page