I recently found a gem on the MSDN forums here for DSL Tools. Eamon of Clipcode Knowledge Services, posted an entry stating that he had written a DSL Tool for the Gang of Four patterns. The source and docs can be found here. Curious as always I took it for a spin and was amazed. It is a cool piece of work. It gives an insight into a lot of code generation and model creation capabilities of DSL. I had some issues running his sample but I have posted a workaround that worked for me here. Look for a post by rupakg at 05/10/2006. Anyone who is interested in DSL should have a look at this excellent code. Kudos, Eamon. Update: I have some issues / workarounds documented here.