When one is evaluating posted answers, we can use the reputation of the "answerer" to help decide the quality of the response for our own purposes. This is done at times when our knowledge is limited and needs to depend upon others as the experts. Of course, up votes are also used in this process. The intent of this request is to add a feature that tempers the global evaluation of users with personal applicability of the answerers skill set.
I would like to be able to add a star next to someone when I have observed that their answers work well for me. Or there might be variety of tags that I could apply to a user. The available tags could be community-defined to prevent outrageous abuse.
This is not the same as the accepted answer to the question "Is there any way to mark a user as favorite?" which is to use "RSS feed".