Yahoo is sharing the love with the development community by offering up a plugin for Firefox and a list of tips to speed up sites. The plugin is cleverly named YSlow and is actually an add-on for the marvelous Firebug. It gives you a new tab in Firebug that shows you performance, stats, and components. The performance tab gives your site’s page a letter grade based on 13 rules for optimizing download times. Each rule gets a grade and has a link to the Yahoo site explaining the improvements that could be made.
The last rule says “Configure ETags” and although I’ve read Yahoo’s entry explaining it, I haven’t managed to implement it. So, if you’ve got advice or tips regarding ETags (or anything else concerning performance optimization) please share!