SharpComments extension by Vitaly Maykovsky lets you change color and font size for individual comments in C# code with a prefix like //! or //+:
Different comment styles in Visual Studio 2010
Comment colors are customizable in Visual Studio options:
Comment color customization in Visual Studio options
SharpComments is a free extension, supports only C# and Visual Studio 2010. You can download it from Visual Studio Gallery.
Making Visual Studio perfect 
cool!
is it possible to extend it with image? //p image.png
Angol,
To insert an image in code you can use the Image Insertion extension.
wov, thank you!
Very nice. Any chance you could do this for VB.NET?
Tom,
I can’t say for Vitaly on future VB.NET support in SharpComments, but there are currently two commercial offerings that provide color comments in VB.NET and C++: VSCommands 2010 and VS10x Comments Extender.
Thank you. I’ve been using this for a week now and it’s working well.
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