Visual Studio Extension I Use at Home

JScript Editor Extensions (free)

This one adds four new features to Visual Studio:

• Brace matching
• Code outlining and folding
• Current word highlighting
• IntelliSense comments

CodeRush

An amazing productivity add-on for Visual Studio. Be sure to watch the demo video on this page. 
There's also a free express version you can try available here with its own demo video here.