Being part of Visual Studio means you have access to a large library of Extensions, both free and paid. These cover a wide spectrum from Tools to Controls to Data:
These Extensions are provided by Microsoft, Microsoft DevLabs, and most importantly by the Community.
You can write your own Extension and provide it for free or sell it to a large global market.
For example, here’s a free Extension that highlights all words that match your selection (a feature not yet available in RTVS):
To install an Extension, go to Tools -> Extensions and Updates: