Hi Spiel,
Carbonite has this.
This is the home of CARBONITE®, a multi feature addon developed by game industry veterans to improve and enhance the game playing experience of World of Warcraft. Our mission is to provide the most feature rich and reliable addon in the WOW universe. We offer a lite version that is free to use and the full version which is available to subscribers of our website.
SO GIVE FREE THE LITE VERSION. BUT IF PEOPLE SUBSCRIBE TO YOUR WEBSITE, THEN GIVE THE PRO VERSION. SO THEY ARE NOT PAYING FOR THE PRO VERSION. THEY GET IT FOR FREE WHEN THEY SUBCRIBE TO YOUR SITE.
CATFISHKNIGHT.