Anti-Spam Registration Question

[joo]

Just use a non-standard captcha system, so the existing scripts won't be able to parse it. As long as it's sufficiently obfuscated, that should stop any automated system from recognising it.

First you advocate for blind people, and then you want captchas with a lot of background noise. Even sighted people have trouble with those.

Good captcha systems (reCAPTCHA for instance) will have audio captchas available for blind people.

It is true that it might be hard to implement it in a way both friendly to screen readers, etc, and hard to parse without the aid of a human, but I don't think it's impossible.

[Chris]

No matter what the system is, some people are going to fall through the cracks. When they get an error message, it should say to contact the admin if they can't get past the step.

Captchas are a nice concept, but they are everywhere now. That means the ones that haven't been cracked yet will be cracked soon.

[EchoMan]

The good captchas are updated regularly to keep ahead of spam bots.

[Joshuamonkey]

I like the "How many words are in this sentence?" idea.