TechCurmudgeon sends this excerpt from an article at Wired: Aaron Foss won a $25,000 cash prize from the Federal Trade Commission for figuring out how eliminate all those annoying robocalls that dial into your phone from a world of sleazy marketers. ... Using a little telephone hackery, Foss found a way of blocking spammers while still allowing the emergency alert service and other legitimate entities to call in bulk. Basically, he re-routed all calls through a service that would check them against a whitelist of legitimate operations and a blacklist of spammers, and this little trick was so effective, he soon parlayed it into a modest business. Last year, his service, called Nomorobo, blocked 15.1 million robocalls.