I came across an article on Digg about an alternative way of showing a captcha using pictures of kittens. This got my brain thinking on how would I devise a better captcha.

My solution is this:

What about putting a sequence of UP, LEFT, RIGHT, and DOWN arrows over a grid pattern. Then the user would just push the arrow keys in the sequence shown. All of the angles would be impossible for a computer to decipher what combination would work – but a human could distinguish the arrows and press accordingly.

It would be like entering the Contra code as a captcha.

This would also work on keyboards worldwide, as non-western keyboards might have characters outside of the English alphabet – but all keyboards have arrow keys (as far as I’m aware).

This doesn’t solve the issue of accessibility for the blind however that all captcha’s suffer from. The best solution I’ve found is an audio file that reads off what’s visually shown. This presents another issue – what language would it be read in? What if you are blind and deaf? What if you have no keyboard? At what point do you stop?

A truly worldwide, accessible captcha – Is it possible?