Update : This works in google chrome too. Press CTRL+B to show your bookmark toolbar. then follow the steps below.

Step 1 : Right-click on the bookmark tab and create a new bookmark.

Step 2 : In the new pop up window enter "Drupal Search" as name and the javascript code below in location.

Code

javascript:(function(){var a="";if(window.getSelection){a=window.getSelection()}else{if(document.getSelection){a=document.getSelection()}else{if(document.selection){a=document.selection.createRange().text}}}var b=prompt("Search drupal.org:",a);if(b!=null){if(b.charAt(0)=='m'&&b.charAt(1)==':'){b=b.substr(2,b.length);window.location="http://drupal.org/project/"+escape(b)}else if((b.charAt(0)=='6'||b.charAt(0)=='7')&&b.charAt(1)==':'){version=b.charAt(0);b=b.substr(2,b.length);window.location="http://api.drupal.org/api/search/"+version+"/"+escape(b)}else window.location="http://drupal.org/search/apachesolr_search/"+escape(b)}})();

Next time you want to search drupal you just click on the bookmark and enter your keyword. To search the api use 6:keyword or 7:keyword. Also you can select any word on the page and click on the bookmark button to search for the selected word.