I was looking through the Mozilla Firefox add-ons section today when I saw this search bar. Looked as though it was just a standard search bar, but I thought I might as well give it a try.
After I downloaded it, I used it a few times and it seemed to work like any other would. Then, by accident I clicked the google logo and I got a list of different sites to search! I went to watch some videos on YouTube, and it offered to add the YouTube video search onto there! Great add-on, and fits seamlessly with my current theme.