SQL Server guru Kalen Delaney, with help from http://sqlserverdvd.com, is offering a series of two-hour DVDs on SQL Server Internals. The first of the DVD series, Lesson 1: Architecture and Metadata, is currently available for $29.95 from http://sqlserverdvd.com. If you would like to save a few dollars, you can watch the DVD for only $14.95 online instead of getting a hard copy.
In the near future, http://sqlserverdvd.com will be offering additional DVD training, including training from Paul Neilson, the author of the SQL Server Bible series.