Carl Bialik from WSJ writes "Captchas -- the jumbles of letters that users must type to gain access to some websites -- are a growing irritation, the Wall Street Journal reports. But programmers hope to make new variations that are both easier to decipher and harder to crack. From the article: 'Some captchas have been solved with more than 90% accuracy by scientists specializing in computer vision research at the University of California, Berkeley, and elsewhere. Hobbyists also regularly write code to solve captchas on commercial sites with a high degree of accuracy. ... Henry Baird, a professor of computer science at Lehigh University who studies PC users' responses to the codes, has been working with colleagues to develop new generations of captchas that are designed to be easier on humans but baffling for computers.'"