Editors' Note: The Download Now link will prompt a local download of the Firefox extension. To install the extension directly, open the file using your Firefox browser.
Whichever Web page you visit, you can use this tool to search Web content linked from the current page. Click the icon in your status bar (a G with a chain-link under it) to open or close the search bar. Or use the keyboard shortcut: ctrl-alt-s. This extension creates an on-the-fly Google Custom Search Engine, based on the links from the current page. Try visiting http://slashdot.org, and then click the icon in your status bar (a G with a chain-link underneath). Enter a query in the textbox, and hit the Search button. You will see search results that are based on the news stories and other linked contents of the Slashdot front page.
Alternately, you can check the Site Search box and search over just the site you are visiting. Accelerator keys are accessed using the Alt-key. For example, when the toolbar is open, use Alt-i to switch to site search. Note that i in Site Search" is underlined in the user interface.