Firefox OpenSearch on popup menu after highlighting text

I consider myself a 'power' FireFox user, but I had no idea you could run an OpenSearch search of text you highlight. It even opens the search results in a new tab! Here's a quick video of the functionality in use, followed by the really easy steps to follow.

Using text highlight search in FireFox from David Sky on Vimeo.
All you have to do is:

  1. Select the OpenSearch plugin you want to use from the drop down in the top right corner of the browser
  2. Highlight text in the FireFox window and right-click
  3. From the popup menu select "Search search engine for "text you've high-lighted"
  4. A new tab will appear in FireFox, with the search results<.li>