Longtime readers may already know that I am a big fan of JetBrains' ReSharper add-in for Visual Studio. I recommend it highly to any .NET developer, but especially to any of those who are interested in being more productive. You'd think that that'd be everyone, but I've found it not to be the case. Many developers I recommend the tool do don't want to learn a new tool, aren't particularly keyboard-enthusiastic, or mistakenly believe that ReSharper is superfluous. On that last point, I've stumbled upon a nice comparison chart showing that that is not the case.
There's overlap, to be sure, but in nearly every instance I've encountered ReSharper's implementation is more thorough and more thoughtful. It's worth every penny.