Add a quoting message system for chat.

Say someone posts something in chat, you could then right click and quote the message easily, directly giving context to what you are saying (As the message would be embedded in your quote on a slightly smaller scale). Maybe even use a linking system similar to boards like 4chan that let you easily navigate through a topic and it's responses.

This would save awkwardly tagging people and trying to refer to the message they posted earlier on in chat to give context to what you have to say.