Menees VS Tools adds several new commands to process selected text, add new text, and work with open files. It started life in 2001 as an add-in for Visual C++ 6, and it has been rewritten a couple of times since for various versions of Visual Studio. Commands include:

Sort
Trim
Statistics
Execute Text
Execute File
Stream Text
Generate GUID
Toggle Files
Toggle Read-Only
Add Region
Collapse All Regions
Expand All Regions
Check Spelling (requires Microsoft Word)
Base Converter (Tool Window)

For more information (including the full source code for the extension) see http://www.menees.com/VSTools.htm.

This software is CharityWare. If you use it, I ask that you make a $5 US donation to the charity of your choice.