Signature

[coloPL]

Hello

I would like to ask about possibility to add username of user who is reading my post to my signature. How can I do that in vB?
To expalin enough I would like to have something like this:
My signature in CP should like :
Hello {here some code} thx for reading my post.

In forum post if my post is reading by e.g. user Lol12
Helo Lol12 thx for reading my post.

somethig like this is available in phpBB by probably BBCode - [you] and what in vB?