These materials are from the talk that Miguel Castro gave in March 2008 at CINNUG.  All the code he showed in the presentation (in both VB and C#) is included. 

Sexy Extensibility Patterns

 Abstract: Let's face it, like everything else in software development, some patterns are cool and some are just plain boring.  So let's turn up the heat and go over some exciting patterns that will allow you to enhance and extended an application without affecting the original design or code.  In this session, I will teach you to design your applications using providers, plug-ins, and modules; in the end making an application as robust and full-flavored as a good beer.

 Bio: Miguel Castro is a principal consultant and trainer with SteelBlue Solutions and specializes in building and teaching how to build, .NET solutions. He is a Microsoft MVP, INETA Speaker, Conference Speaker, contributor to CoDe Magazine and DevSource.com, as well as an active blogger, and has been a software developer for over 20 years. With a Microsoft background that goes all the way back to VB 1.0 (and QuickBasic in fact).  Miguel has spoken at numerous user groups, code camps, and conferences around the country.  He has also been featured on the Internet Radio Talk Show, .NET Rocks, .NET Rocks-TV, Microsoft’s ARCast (Architecture Podcast), and The Polymorphic Podcast on numerous ocassions.  His blog and other things of potential interest can be found at http://www.steelbluesolutions.com/, where you can obtain his new CodeBreeze code-generator.  He currently resides in Lincoln Park, NJ with his wife Elena and his daughter Victoria.