I speak at user groups on a regular basis and have some presentations people might find useful. The downloads all come with slide decks and sample applications.
Multi Threading in Microsoft .NET (Visual Studio 2003)
http://njmsdev.org/Meetings/2004/2004-2-5/MultiThreadingInMicrosoftDotNet.zip
Generics and Iterators in Microsoft .NET 2.0 (Visual Studio 2005)
http://www.setfocus.com/N3UG/Past/Generics.zip
This was created using beta 1 of Visual Studio 2005; one of the samples doesn't compile using the VS 2005 RTM.
Reliable Message Handling (Visual Studio 2005)
http://www.setfocus.com/N3UG/Past/ReliableMessageHandling.zip
An examination of message queuing using MSMQ.
Debugging Tools for Windows (Visual Studio 2003)
http://njmsdev.org/Meetings/2005/9-1-2005/DebuggingToolsForWindows.zip
An examination of Microsoft's Debugging Tools for Windows package.