Just because you didn't get to go to that awesome conference doesn't mean that you can't still watch the lectures! Each weekend, we'll feature a recommended web development lecture on Nettuts+.

In this talk, hosted by Thomas Fuchs at JSConf, he reviews a handful of tweaks that can be made to your JavaScript to drastically improve performance (at least in terms of percentages). Along the way, he covers why you shouldn't pre-optimize your code, how each browser's JavaScript engine excels in different areas, and even how simple things, such as reordering your expressions can increase performance by a significant amount.