from RiffTrax:
RiffTrax wants your jokes! We’ve provided you with some choice clips from Reefer Madness, along with 10 different spots for you to write jokes to get included in our LIVE broadcast of Reefer Madness! The winners (picked by the guys themselves) will receive a RiffTrax Swag Bag and have their names featured on-screen when their joke is said!
More info here.