See the demo on AreYouHuman.
It offers an alternative to CAPTCHA.The site claims its "PlayThru" technology is the next generation of online human verification.
It is more simple, more intuitive, the current CAPTCHA options.
It uses different game mechanics to interact with the user and definitely more enjoyable than awful squiggly text.
The site runs a story in its "About-us" section talking how this idea got clicked!
The site also runs a slide show on World's worst CAPTCHA
Would it be able to replace CAPTCHA?