Rated 4 out of 5 stars
This add-on is very useful to find information on web sites that are too often changed to be reliably searched using google or yahoo. Or you can open search results in tabs and then close all the tabs with wrong words (starting with the highest tab number).
Find in Tabs is the reason why I now switched back to Firefox 3.5.11, because as smayer97 and petrus3 pointed out, it is useable in 3.6.x (3.6.7), but one thing did not work correctly:
When Find in Tabs results were open, they always used at least half of my screen (1400 x 1050), moving down the split line just gave a gray area instead of the web site. It would be great if this small error could be resolved by the developers.