* in Photoshop - "save for web" and let it figure out what it thinks is optimal * YSlow for Firebug to see if anything is really loading slowly / being gross

* in Photoshop - "save for web" and let it figure out what it thinks is optimal * YSlow for Firebug to see if anything is really loading slowly / being gross * Like you mentioned, YUI Compressor to minify/compress CSS and JS * We use Symfony so the Symfony dev toolbar to profile slow SQL queries and generally see what is causing pages to render slowly. * Lately, Firebug's NET panel to monitor what requests are taking the most time.