How Do I Use the ASP.NET AJAX AlwaysVisible Control Extender?
Published January 13th, 2009 Under Coding, User Interface | Leave a Comment
See how easy it is to anchor a page element to a position on screen, where it remains always visible no matter how far the user may scroll the document. The floating page element may be anything from static text to an AJAX-based, context-aware help box.
http://www.asp.net/learn/ajax-videos/video-86.aspx