VS2010 Spell Checker Extension - spell check your strings and comments while you code
I have found this really great VS2010 Extension.
After downloading it, run it and restart your VS2010 environment.
This extension spell checks your comments and double quoted strings while you code.
Please note that it doesn’t work with a right click context menu (as in Microsoft Word and other tools) but it gives the caret down with spell checking suggestions.
It’s free of charge and is something I’ve been looking for a long time.