Originally Posted by Chief

At the very least you'd want to set it up like www.domain.com/hot/ (and iframe the promo code there) on the main domain. Otherwise register some seperate domains for each campaign and advertise them and have each one redirect to the relevant refcode (though of course you'd loose some branding this way). But I think it would hurt you to have the URL as domain.com/?refid=2323 or something like this in your print campaign.