I sometimes have clients that need to update legacy applications to integrate with newer technologies (e.g. .NET) - this article: Visual Basic Fusion: Best Practices to Use Visual Basic 6 and Visual Basic .NET Together - on the MSDN site is of particular interest for those types of purposes. One client in particular has an ASP 3.0 based application that has some challenges coming up in the near future to integrate their commercial product offering with their own clients .NET applications.
I've been diving into a broad variety of topics related to Service Oriented Architectures (SOAs) lately - and some of the following topics have been quite interesting reading:
For those who may find those topics too heavy - and who need a kinder-gentler introduction to Web Services, I found this presentation to be apt for helping less experienced team members get up to speed on the concepts revolving around Web Servcies:
A few SOA articles that I've read recently: