It's too early in the morning to think of creative punishment methods for rapists. I'll get back to you on that. Perhaps a codpiece with razorblades inside...
Sex offenders (including rapists) have the highest recidivism rate among released prisoners. In other words, they are the most likely to commit the very same crimes again, even after they've done hard time. Why should we not remove the instruments they used to commit rape? It should also be viewed by a festive public audience. Sometimes old school methods are the best.
Maybe we could put that on pay-per-view and tax the proceeds. Think about the thousands of people who flocked to public hangings in Victorian England. To use a modern example, consider the millions who spend $10 apiece to see films like Hostel and the Saw series. Passion of the Christ was basically a snuff film as well, and look at the profits. If we did that, our criminal justice system would soon pay for itself. So in one stroke we accomplish two things: rapists get what they deserve in the form of a deliciously ironic punishment, and we get out of the recession. Yes, yes, I know I'm a financial guru.
Man, we need a pair of these guys in every major US city.