Atlas: ModalUpdateProgress - An UpdateProgress Control in Modal Popup Style
ASP.NET AJAX has a cool UpdateProgress control that provides a visual indicator while one or more of the UpdatePanel controls are being updated. However, it will be much more useful if all other elements on the page could be disabled when the UpdateProgress is shown. This led Ting Huang to build the ModalUpdateProgress control in which the UpdateProgress will act as a modal popup.