Reference ticket A from ticket B's notes?

Is there a way to reference one ticket from the comments and/or actions of another ticket? I’m hoping for something like the pingback behavior of GitHub issues and commits -- when I tag ticket A in ticket B, not only do I get a hyperlink to ticket A in ticket B, but ticket B also gets a reciprocal link back to ticket A. That would be the biggest win.

But for now I’d just love an easy way to reference another ticket with a hyperlink.