Many subscription and memberships sites owners know that events and conferences are a great way to add Benjamins to your bottom line (well, Madisons, really). And perhaps during your speaker recruitment, a couple of presenters asked if they could use Prezi.Now Prezi has many virtues, including creating some dynamic presentation. But Justin Rondeau, Editor of our sister publication Which Test Won, recently informed me that if you're using the free version of Prezi, everything you create will be m...