Gmail Addons Embeds Any Webapp in Gmail

Firefox with Greasemonkey: The Gmail Addons Greasemonkey script embeds any page you specify inside Gmail’s interface. By default, it comes with Google Calendar and the Google Talk gadget. (If this sounds familiar, it is—Gmail Addons is an update to the previously mentioned Enhance Gmail script.) Add any other web pages to Gmail by following the directions on the script homepage. If you’re willing to dig into manually editing the script, Gmail Addons can embed Google Reader, Notebook, Docs, Remember the Milk, or virtually any other web page you’d like next to or below your inbox. Gmail Addons is free, requires the Greasemonkey extension to run.