As the ubiquitous (and crappy) IE browser begins to wane in popularity, it’s increasingly more important for developers to focus on cross-browser development. “Works on my machine” just isn’t a suitable answer anymore folks.
Inquisitor, the popular Safari search tool is now available for Firefox. Nice. There’s also an IE beta available if you’re still stuck on Internet Explorer for some reason.
Source : http://www.inquisitorx.com/firefox/index_en.php