This isn't really a vB addon, so I decided to post here instead of as a release
This little mod lets you search your vBulletin 3.5 forum directly from within Firefox, using Firefox's quick search box (to the right of the Address box).
It adds an option to the dropdown menu in that box to search your forum.
Installation:
Extract the zip file to:
Code:
C:\Program Files\Mozilla Firefox\searchplugins
(or whereever the correct folder may be on your system

)
Now edit the vbulletin.src file using any text editor. You need to edit the following 2 lines:
Code:
action="http://www.your-website.com/forum/search.php"
searchForm="http://www.your-website.com/forum/search.php"
Edit these, and put your website / forum path in there instead.
Once done, save the file, load Firefox, and it (should) appear in the search dropdown
Alan.