I was thinking that Kickstarter could be used by Rifftrax to fund the production of some long-time most wanted Rifftrax that they have been afraid to do because of a fear of low sales. I am thinking of films like Dune, Super Mario Brothers, or Billy Jack.
Just set the goal to whatever the break even point is for a Rifftrax. That way there is no risk for them and all the sales after that would be gravy.