Wolfram Alpha Google is a Firefox addon that shows Wolfram Alpha results whenever you do a search on Google.
Over 100,000 downloads and counting!
You can also check out the source code on Google Code.
Wouldn't it be nice if you could get's "computational knowledge" at the same time as Google results? This makes it so.
The Wolfram Alpha Google add-on for Firefox lets you run a side-by-side comparison of results from Google, and the new Wolfram Alpha search engine.
My favorite use for it is to pull up nutritional information for fast food and cast lists for movies.
The Google results come in at a normal speed, while the Wolfram Alpha ones catch-up on the side.
The most interesting WA-related plugin is aimed at those users who really love the service; so much, they want to merge it with Google.
If you love having extra goodness packed into your searches, then you will definitely enjoy using the Wolfram Alpha Google extension!