Inheritance Margin by Sam Harwell adds special glyphs to virtual methods and properties in the Visual Studio 2010 editor. For interface methods it adds the I glyph and for virtual methods it adds the O glyph:
I glyphs for the interface method
O glyphs for the virtual method
When you hover the mouse over a base glyph it displays what types implement or override this method or property:
Implementing properties tooltip
Overriding properties tooltip
When you hover the mouse over a derived glyph it displays all base methods that are overridden:
Overridden methods tooltip
Inheritance Margin currently supports only C# and Visual Studio 2010. You can download this free extension from Visual Studio Gallery.
https://tabsstudio.com/
Making Visual Studio perfect 