It is necessary sometimes to create an extension for VS that should be used by all developers in a team. Well, you have to remember to update it when new version arrives. It would be better to have these extensions as a scripts included in solution.

So, for example I want to provide some custom command for css folder in my web project. I create a script (in powershell for example) that implements this command. Include it to project's special folder "extensions". This command will be available automatically for all developers when they checkout the code from repository.