Microsoft now has five application blocks (thanks to SBC on .NET Weblogs):

My experience with the Data Access block has been great.  It was easy to modify for typed DataSets, though the new version 2.0 supports them natively.  The Exception Management block has been pretty good, but the sample code for the email / log file publisher neglected to mention the fact that I needed to develop code to iterate through all the inner exceptions.  Without this, you just continually get UnhandledHttpExceptions if you are developing a web application; not very helpful.  If the exception stack walk code was included, it would be a home run.