First you will need AcidSearch which is a cool little app that mods the search box in Safari.

  1. Click the small mag glass in the search box
  2. Click ‘AcidSearch Preferences’ at the bottom
  3. Click ‘New Channel’
  4. In the ‘Prefix URL:’ field enter
    ‘http://en.wikipedia.org/w/index.php?title=Special:Search&search=’ (Without quotes)
  5. Your Done

P.S Gonna be jazzing up the site a little so keep an eye out and tell me what you think.