iGoogleBar is a Firefox extension that enhances Google's navigation bar by showing the number of unread Gmail messages (only from the inbox) and the number of unread posts in Google Reader. The extension also adds icons that open Google gadgets for each service so you can preview your Gmail inbox from Google Calendar or open a recent document from Google Notebook.
For example, in the screenshot below, I visit Google Docs, but I can see that there is a single new post in Google Reader, only two unread messages in my inbox and I can easily open a bookmark from Google Notebook.
Unfortunately, the new navigation bar is displayed after the page loads, it works only in Google's communication apps and it doesn't include the More dropdown. Another big drawback is that the extension is actually a Chickenfoot script that comes with its rendering engine, which is terribly slow. In fact, the extension's XPI file has 1 MB, almost the same as Google Toolbar for Firefox.
{ via Googlified }