Exit Popup

I am looking for javascript/jquery which will show a modal form when user tries to exit from a webform.? This popup page will have some text and one textbox. The popup will look something like this <[login to view URL]>? (click on the button to see the popup). This kind of popup box (with a textbox and message) will soon as soon as user clicks on the back button or tries to close the tab/window. Please bid only if you already? have the solution to this so that you can send me the solution asap.? This is just to prove the concept. Please send me the link...I want to make sure that you are not doing something like this <[login to view URL]> thanks