What are your top Visual Studio 2010 extensions? [duplicate]

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Best VS2010 Extensions

Visual Studio 2010 - recommended extensions

I've just discovered JSEnhancements for Visual Studio开发者_开发问答 2010 and it's left me wondering what other "indispensable" extensions and add-ins there are that I might benefit from.

What are your key productivity extensions for Visual Studio 2010?

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JetBrains Resharper. It's not free, but it's surely the best around.

Edit: I also like TestDriven.NET. And it's usually free.