Users of the excellent Firebug debug tool for Firefox probably also uses YSlow, a performance analyzer from Yahoo! It gives good tips for decreasing page load time such as gzipping static files or combining javascript files. Google has now released a similar add-on for Firebug called Page Speed. It is very similar to YSlow but it also introduces a new tab feature called”Page speed activity”, a request overview, and in addition to giving performance suggestions it also tells you the improvements of implementing the suggested changes.