UNBLOCKABLE OnClick Full Size Pop-Under

We are looking for a javascript expert to write an unblockable javascript onclick pop-under code. Code will be loaded on the page ad follows: <script type="text/javascript" src="url"></script> All the code should be inside that file including a var called "url" where the pop-under url will be. Window should open when the user clicks anywhere in the page as a pop-under with full window size. It MUST work on any browser, Firefox, IE, chrome, Safari, Opera, etc. We will take 2 winners, both will be paid as we will use the best code provided. Must be tested with all browsers before being sent. Project is URGENT.