I hate to be the party pooper here but this is not going to happen. It's a good idea, but the problem is that, just like all software, our forum software has limitations. We cannot simply have whatever we want, unless that option is part of our forum software or there is a plugin made for that purpose. In this case our forum software doesn't have this option, nor is there a plugin like available, which means that this suggestion is not possible.
Only way to do it would be to spend hours coding that plugin ourselves, and since this feature is not crucial by any means, I don't see the point in making that plugin.
Short version:
Good idea, but unfortunately not going to happen.