Plugin to display only certain user level or select users in sidebar?

I’m just wondering if anyone knows of a good plugin that will allow me to display just select users, or a certain user level (and above) in the sidebar?

I’m using P2 theme as an open forum of sorts, but with a “Genius Bar” to answer questions. I’d like to display those who are on the “Genius Bar” only, and not people who just register to ask a question. I’ve found many plugins/widgets that will display multiple users, but they make you exclude those you don’t want, rather than simply include those you do. I don’t want to have to go in and exclude every new user that signs up.

Thanks much for any ideas!