5M17H

I know thats a stretch to explain so I'll just put a pic up.
I just created and will be managaging a PHP Bulletin Board so I would really like to be able to use this feature.
Even if I can't use this feature, I would really like to know more about it so that I can suggest this feature to other forum administrators. I think it is really handy
Might it be a style related feature?

Anyways, I'll give kudos to Mr. Stone and Vbulletin for the design and style of this forum. I really like it.
This is a default feature of vB 3.x. I think there's a hack for vB 2.x, but I have no idea about PHP BB. Sorry.