Web Performance/Profiling Techniques - Best Practices

http://code.google.com/speed/page-speed/docs/rules_intro.html

Optimizing caching — keeping your application's data and logic off the network altogether

Minimizing round-trip times — reducing the number of serial request-response cycles

Minimizing request size — reducing upload size

Minimizing payload size — reducing the size of responses, downloads, and cached pages

Optimizing browser rendering — improving the browser's layout of a page