Need Custom Exit Popup Script

Hi there, I need an exit pop up to go on this site here: [login to view URL] I have an exit popup there now, but it doesn't give me the desired functionality. If someone tries to close the page or navigate away, I would like to have an exit pop-up slide down from the top. I should be able to put content in the pop-up and more importantly have an optin form on the exit popup, similar to the entrance pop on this site: [login to view URL] If the person still tries to close the page, it should redirect them to a url of my choosing. The exit pop up should NOT open if the person submits the normal optin form on the right hand side, it should not obstruct it. Very important, this should be fully functional under all major browsers and versions such as IE, Firefox, and if possible Safari and Chrome. Thanks very much, please quote your price.