http://www.webpagetest.org

https://www.cloudflare.com

http://pagespeed.googlelabs.com/pagespeed/

http://technicallyeasy.net/2008/10/increase-you-web-site-speed-with-htaccess/comment-page-2/#comment-33869

http://code.google.com/speed/articles/

http://developer.yahoo.com/performance/rules.html

 

http://www.askapache.com/htaccess/apache-speed-expires.html

 

http://pagespeed.googlelabs.com/pagespeed

 

http://code.google.com/speed/pss/