I am familiar with most of them at a superficial level, having a while ago, read an equivalent article from a Yahoo Geek about how they optimised their webpages.
I was particuarly interested though in this article as it explains, with graphs – the improvements to be had from multiple hostnames on webservers.
I already tend to use Gzip on my main websites and am going to be engaging in a total rebuild of the main buisiness website early next year – right down to a complete new server and installation.
I will keep this article on file as it makes sense to split out my static and dynamic content and images into seperate hostnames to speed up delivery.
One other idea I saw a while ago for websites with a lot of small images was to actually serve a single large image containing all the components – then use CSS to crop the “master image” for each use so that only the required part was visible.
That is a great way to cut down the multiple HTTP header request overhead to a single request. While not relevent for my websites, which tend to be graphics light – I thought it was a very interesting idea.