Platform: Windows XP, Windows Vista
Number of downloads: 17161
It offers instant access to a variety of Google facilities, and provides access to the Google search bar, although this is already integrated into Firefox.
Further buttons allow you to access Google's image search, Google Groups, and its web directory.
There's also a graphical bar representing the page rank. This is Google's measure of a page's quality, defined as one which has more links to it from other sites.
A form filler is included for easy completion of online forms, and a spell-checker ensures the your spelling is correct should you choose to enter details manually.
Also included is WordTranslator, which instantly translates English words on websites into other languages. Simply choose the language to translate to, and the translation appears in a tool-tip when you hover over a word.
This is the Windows version of the Firefox extension. Linux and Mac OS X versions are available from the Google Toolbar webpage.
Note that by downloading Google Toolbar for Firefox, you're adhering to the extension Terms & Conditions.