Meet "Snapback". "Snapback" is a symbol which is automatically generated by the quoting system, but can also be manually used, manipulated, and inserted into posts.
Here's an example of a snapback reference, generated after quoting someone:
CODE
[snapback]1487[/snapback]
The number refers to a specific post (the one being quoted), and clicking on a snapback throws the user back to the quoted post. Click the little icon below to see it in action.