2) use CDN's wherever possible
3) use scripts at the bottom of the page (http://developer.yahoo.com/performance/rules.html)
4) CSS sprites for images
5) http://yuiblog.com/blog/2007/01/04/performance-research-part-2/
6) Add an Expires or a Cache-Control Header
7) Put Stylesheets at the Top
8)Make JavaScript and CSS External
http://www.jquery-asp.net/blog/squishit-javascript-and-css-compressor/
YUI
http://www.mattfitz.info/library/article/86