vB permissions on a non-vB page?

[thuffner]

I was wondering how this would be implemented.

I currently run ads on both my forums and every page of my website. I was wondering how I would go about "getting rid of" the ads on both the forums and every page if the user was registered to the forums.

EDIT: To be specific, I would like to be able to use this if statement on a non-vB page:

<if condition="$show['guest']"> Stuff that only a guest sees. </if>

Any ideas? Could someone point me in the right direction?

Thanks so much.