I and six of my peers are hosting a regional, annual conference for librarians and teachers on the joys of liesure reading, called 'Books Abound', October, 2007. We anticipate 125 attendees. As an icebreaker we thought trading cards would be fun. Collect a set and win a chance at a prize!
But trading cards are a little harder than first thought. A set of 12 to 16 cards might be nice, on a literary theme, character, etc., but no such animal, to my limited research exists for easy creation/acquisition.