Firefox has a search box separate from (to the right of) the address box, and has a
mechanism set up for populating it. CPAN has an entry already, and perldoc does too. They've got them for ebay, pricegrabber, half.com, wikipedia, dictionary.com, ... the list just goes on and on. It seems a little silly to roll your own mechanism for Firefox.
Caution: Contents may have been coded under pressure.