Actually, the button you are referring to is the Post Award button, which is a feature only available to Founding Members.
This is explained in the Founding Members thread:
Quote:
Originally Posted by 711
Founding members also have the ability to give HQD Post Awards to other members for exceptionally helpful or interesting posts. The Post Award icon is at the bottom left corner of every post, right next to the reputation scales. The HQD awarded via this method are drawn from the forum cental account, not the Founding Member's HQD balance.
