http://www.dralegal.org/cases/private_business/nfb_v_target.php

The above link is to a news story that shows what is coming. Target a private company was sued over web accesability. Now the EU and the US government have their laws that thier sites must be accesable to the deaf mute and blind. But this law suit sets a leagal presidence for private sector sites.

http://en.wikipedia.org/wiki/Captcha

Captcha for those who do not know is the image you get when you sign up for sites. You have all seen them. The funky letyters and numbers that you must type in to prove you are human. Great idea, but it has its faults.

Number 1:
It has been broken. You read that right. You have to have some fairly distorted letters, blended colors and other funky crap to be fairly(notice I didn't say 100%) sure a bot will not be able to read it.
Read this: http://en.wikipedia.org/wiki/Captcha#Computer_character_recognition

Number 2: The blind are screwed. Thie disabled community are very offended by captch. Some of you say how do the blind surf the web? Look up screen readers. The one that comes to mind is JAWS http://www.freedomscientific.com/fs_products/software_jaws70fea.asp
http://www.netmechanic.com/news/vol4/accessibility_no14.htm

So you have security that unless you really put some thought into it(not used the code from zend.com or php.net) is pretty useless. And you lock out a growing section of netizens. What is the answer? The human brain. Computers do not tell jokes, they do not know cliches, Sure you can program them to have a pool of each to pull from, but how many can that pool effectivley hold?

Imagine a mod that allowed site admins to offer audio, video, image, text puzzels to prove human inteligence. The admin could upload a middi file that sounds like a top 20 hit. It plays you type in the band, or maybe the song title, or maybe it is random the info needed from the same audio bit.

Text could be simple things, why did the chicken cross the road? "to get to the other side".

Yes I know a bot can be coded to answer that. But if every admin could set up thier own questions, images, videos, audio, how efective is it to code a bot for one site? Then the admin changes everything. The bot is useless.

The user is offered a choice on authentication. Anyone intrested in Section 508 US government accesability compliance, here is the horses mouth
http://www.section508.gov/

and take a look to:
http://www.ubbcentral.com/forums/ubbthreads.php/ubb/showflat/Number/165898

Yeh, way to go Russell, you have Rick rethinking himself :x...

The question idea is cool, but might I make a sugestion. Get more milage out of a question with a tad more code. Say you have a question,

What color is an orange?

Now say you have 3 categories of answers for this question. With some basic css you could position some instructions hard for a bot to read. Like

Type out the second word in the question
Answer the question
what is the 16th letter in this sentence.

Now you have 3 answers for one question.

The instructions are text in a PHP generates a random string to go into the "id" attriburte. Then generates a css blurb for that name. You could even move the instructions around the page.

Question, how does a blind guy know what colour an orange is?

if he is 5 or older he would have heard it. Most users of a BBS are say 13+ years of age. If you agree with that, then you must assume some life expeirences with resonable human contact.

The person may be blind, nut would know the smell and taste of an orange most likely. At some point... "Is it orange like the color" had to come up. The person is blind, yes... But you have to remember they are still social and communicate.

One might argue no one knows what color an orange is since all we as humans see is the reflecting and refacturing of white spectrum light. But we have a concept of it. So will the blind guy.

"The orange tastes blue!" lol...

And not nessessarily 13+, I know plenty of parents who allow their 8 year old's online ...

Okay describe the texture of this, Cactus:prikley,spikey,pokey

Where Cactus: is the item and all the answere are split() via comma into an array of acceptable answers.

$answ[0] = 'prickley';
$answ[1] = 'spikey';
$answ[2] = 'pokey';

You can do a for each to run though all answers and compare against user input.

So each admin could allow multiple answers to multiple questions. And you have on question with multiple add ons

i.e. Cactus:

That would make coding it a bit easier and easy to add to for admins.