In a recent post to his blog Anson Cheung guides you through another tool that can help you optimize your web applications - using YSlow for the frontend to detect trouble spots early (whether they're actually caused by the frontend or not).

He goes through the thirteen rules to help improve your website's performance including:

• Make fewer HTTP requests
• Gzip components
• Make JS and CSS external
• Remove duplicate scripts
• Configure ETags

For more information about the YSlow extension (available for Firefox, Chrome, Opera and mobile devices), check out the project's page on Yahoo's Developer section (including ten more rules it checks).