Time wasted on CAPTCHAs:
You knew it had to happen. Someone had to go figure out how much time we waste typing in CAPTCHAs to gain access to
websites.
It’s how they can tell if you’re human or a robot.
“Humanity is wasting 150,000 hours every day on these,” said Luis von Ahn, an assistant professor of computer science at Carnegie Mellon. He helped develop the CAPTCHAs about seven years ago. “Is there any way in which we can use this human time for something good for humanity, do 10 seconds of useful work for humanity?”
http://www.cnn.com/2007/TECH/05/29/blather.to.books.ap/index.html