If you use or are planning to use EntLib on your projects, you have to be excited about the integrated configuration editor now part of EntLib 3.0.  This is one of the coolest features in this release.  One of the pains with Entlib is the many config files it requires you to manage, and often edit by hand.  Now you can just double-click on any config file (even app.config!) and open it in VS.  The installer sets it as the default editor, but if that doesn't work for you, you should find it in the Open With... list.

Find out more about EntLib and download the latest release here.