Search Cloudlet is an Firefox addon that inserts context-aware tag clouds into a traditional Google and Yahoo search interface to help you navigate more efficiently through search results. Here's how it works: You enter a search term and Search Cloudlet works by looking at the words, sources, locations and other data in the search results to create a weighted tag cloud — the bigger the term the more frequently it pops up in the results. To filter your results just click a tag and the page will reload with that word included in the search. Then you'll have a new cloud with new terms and you can keep narrowing from there.
You can also click the Sites tab to show a list of web sites featuring content matching your query. So if you want to limit your search to say, Wikipedia articles, just click on the Wikipedia link. The Net tab lets you limit your search by domain type, such as .com, .org. or .net. And if you want the tag cloud to go away all you have to do is click the off button.