Ayende Rahien will be giving a course on buliding DSLs with Boo in Austin on May 19-20. I'm a closet fan of Boo, having lurked on the mailing list for about 6 months, and really looking forward to getting a stronger grasp of the language, and the benefits of building your own domain specific languages. This is a great opportunity to learn from the preeminent creator of Boo DSLs.

Scott Bellware sent a good writeup to the AgileATX mailing list:

This class takes you deeper into the reasoning and power of dynamic
programming on the CLR.  It will show you how to build and take
advantage of DSL's for your own CLR applications, and why DSL's and
language-oriented programming are such a valuable practice at this
point on the programming timeline. 
You'll leave this class having been jump-started on a new, powerful
language and paradigm, and be connected to other motivated .NET folks
who are working toward bringing some of successes of dynamic
programming communities into the .NET community.

The class will also give you the opportunity to check out a town that
folks are starting to recognize as a progressive and leading .NET
competency in North America, and to have some fun with Austin's
developer community folks in lush green and sunshine of Central Texas.

There are still some spots open, if you are interested you can register here.