Google Tag Cloud Maker is a Greasemonkey script that aggregates all the words from the titles and snippets of Google search results and creates a box that lists the most frequent words. If you hover over one of the words, you'll see the search results that contain that word in the title or snippet and if you click on the word, it will be added to the current query.

To install the script you need Greasemonkey for Firefox. Find more Greasemonkey scripts for Google services at this site.

Lifehacker | Google Operating System

Google, Google Search, Google Tag Cloud Maker, Greasemonkey, Script, Firefox