mk1004 writes: Yahoo news has an article explaining how the text-based CAPTCHA is giving way to ad-based challenge/response. It's claimed that users are faster at responding to familiar logos, shortening the amount of time they spend proving that they are human. Link to Original Source
You can do this in a number of ways. IBM chose to do all of them.
Why do you find that funny?
-- D. Taylor, Computer Science 350