Slightly WordPress centric, but great introduction and tutorial on one page about page speed.
Great resource site with articles, tools and more on web performance matters. Much like this site, but probably better ;)
Case studies and experiments demonstrating the impact of web performance optimization (WPO) on user experience and business metrics.
Multiple images being loaded in a CSS file can be mitigated (for modern browsers) using Data URIs. This is one of the better articles explaining the process and links to an online converting tool.
Chrome, along with FireFox, are looking for was to speed up website experiences in the browser by adding cues to the HTML.
Using some of the tools and methods already linked to here at sitespeed.com.au, ReadWriteWeb outlines some great tips.
Comprehensive tutorial on web caching with tips that help optimizing for speed.
Google’s comprehensive documentation on best practices for site speed. Covering many of the steps involved in page load time, including resolving DNS names, setting up TCP connections, transmitting HTTP requests, downloading resources, fetching resources from cache, parsing and executing scripts, and rendering objects on the page.