Here is the latest in my link-listing series. Also check out my ASP.NET Tips, Tricks and Tutorials page and Silverlight Tutorials page for links to popular articles I've done myself in the past.
Displaying the Number of Active Users on an ASP.NET Site: Scott Mitchell continues his excellent series on ASP.NET's membership, roles, and profile support. In this article he discusses how to use ASP.NET's Membership features to estimate and display the number of active users currently visiting a site.
ASP.NET Dynamic Data Update: The ASP.NET team last week released an update of the new ASP.NET Dynamic Data feature. This update adds several new features including cleaner URL support using the same URL routing feature that ASP.NET MVC uses, as well as better confirmation, foreign-key, and template support.
Hope this helps,