Hardest captcha ever?
The hardest captcha I've come across is the audio one used by Google on <a href="https://www.google.com/accounts/NewAccount" rel="nofollow">https://www.google.com/accounts/NewAccount</a>. Click the little wheelchair icon to hear it.<p>It's so hard to decipher, it almost comes across as a cruel joke at the expense of blind people.<p>These are much easier, in that I can actually understand them.