Would you Warranty Your Email?

Kurt writes "A team from the University of Michigan is proposing an economic solution to spam. Instead of relying on technical solutions or government regulations, they use a sender warranty system. In some cases, they argue, it can even be superior to a perfect filter with zero cost, and no errors. Their working paper is available at SSRN. With the caveat that some infrastructure is necessary (isn't it always?), they also claim their approach restores control to the recipient, halts spam, and creates a marketplace for valuable information exchange."