Feature Request: Selective Broadcasting in Channel

Back when I ran a Ventrilo server for my WoW guild, there was a way to modify your push-to-talk key so that when you pressed both it and the modifier, it would only broadcast your voice to specific people tied to that key bind. 

I used to use this feature to speak to the officers in the Raid, without having to drag them to different channels to speak in private. That way no one really knew there was a separate conversation happening and made good use of our limited play time. I could see this being a server specific or user specific setting depending on how it would be implemented, but I think User specific would probably be most ideal, so that if you bring friends with you to a new server, or make new ones there, you can still have your own conversations while taking part in the general chatter of the channel.