The best thing about Firebird not having an installer is that you can run it on public computers that don't allow new programs to be installed. The delight and calm that descends on opening up Firebird after a week of IE popups, crappy toolbars, random home pages, lack of tabs and "WHY does it have to reload the same page in a new window" was remarkable. The only things they need to get rid of are the default Mozilla branding - toolbar bookmarks, Firebird home page - then it'd be just perfect. Maybe a one-click 'clear history/cookies/form fields/cache' would be handy as well. The search box should really default to Google, like in Safari, too, and the throbber needs to be between the search box and the address field by default, so you can see when something's happening.