While hunting around for a new ASP.NET AJAX book I ran into these two excellent posts.
"Scott Gu's, ASP.NET Gotchas and Guides":http://weblogs.asp.net/scottgu/pages/ASP.NET-2.0-Tips_2C00-Tricks_2C00-Recipes-and-Gotchas.aspx
"ASP.NET 3.5 goes Open-Source":http://weblogs.asp.net/scottgu/archive/2007/10/03/releasing-the-source-code-for-the-net-framework-libraries.aspx
"Jeff's Junk, .NET Musings":http://weblogs.asp.net/jeff/default.aspx
Good stuff, well done guys!