For dealing with complexity of a different sort - enterprise architectures - see Roger Sessions' new white paper in the MSDN Library: A Comparison of the Top Four Enterprise-Architecture Methodologies. I'm sure there are some parallels I can find with my problem (Managing Complexity) and ideas I can borrow. It's also interesting to see in his conclusion that it's less about choosing one methodology and more about mixing the right blend, much like software development methodologies.
Twenty years ago, a new field was born that soon came to be known as enterprise architecture. This paper covers a broad introduction to the field of enterprise architecture. Although the history of the field goes back 20 years, the field is still evolving—and rapidly so.