I am a big fan of JetBrains Resharper for .Net development. It saved me a ton of time refactoring and documenting a large project recently.
Granted, I just spent about two years doing Java dev in IntelliJ and recently moved back over to working with C#. I'd gotten pretty used to working with IntelliJ so that probably colors my viewpoint a little, but the JetBrains IDEs do have some features I really like - the class structure pane, for example, is really useful.