CAPTCHA, good thing or bad thing? We all run into them and get very, very annoyed when they don't work right. And we have all noticed they have gotten harder and harder to decipher. Although we have to give these little boxes of injustice credit, they have slowed down the spam to some of our inboxes and hacking our passwords. This all came up after reading a great article today (http://www.webdesignerdepot.com/2013/02/recaptchaing-the-importance-of-ux/)

You also have to be careful of which one you use because spammers are sneaky, which is why they do what they do. If you use something that just images as letters, or something with a few strikes through the letters this will not always work. OCR has come a long way and can be done easily with these.

So lets cover what we have available to use..

reCAPTCHA
http://www.google.com/recaptcha

First, I bet you didn't know Google had their hands in this pot. Don't think of this as a money maker for this, this is part of Google's awesome plan to digitally archive the world.

So it's not that reCaptcha is trying to push some nasty hard to read words at you, it is actually trying to help archive something Google has not been able to OCR and digitally archive. So in all actuality, don't hate it, appreciate it! It is doing good for the world. It may be annoying but it is helpful. This is also depending on your audience, if you are going to have impatient or visitors that would have trouble deciphering the words, then you might want to consider an alternative.


 
Visual Captchahttp://visualcaptcha.net/
This is really a nice change of pace, it's very hard to get this one wrong. They also claim to be very mobile friendly.  I tested it on my Galaxy S3 and it worked very well. You don't have to drag it, just press on the right object and it drops into the circle. It is easy enough to implement and is built on our ever favorite JQuery (Supports 1.9 and under) and uses PHP. This also means you could technically mess around with the source and have some customizations to it.


Securimage
http://www.phpcaptcha.org/try-securimage/

As I was talking about OCR and you have to really cover the letters, Securimage really stood out. Somehow the codes are still legible but very covered. I took it through some OCR tests using Acrobat Pro X, which does a really, really good job at OCR and it failed miserably. It's very lightweight and based on PHP so it can easily streamlined into any code or CMS.

MotionCAPTCHA
http://www.josscrowcroft.com/projects/motioncaptcha-jquery-plugin/

This one is beautiful. Written by Joss Crowcroft it utilizes JQuery yet again to make a very elegant way of determining if the form-filler is human. Granted someone could code a way around this, but this one is fun and can be touch screen friendly. I give it total innovation points!


DigitalSpin
http://www.digital-spin.com/demo.php

This is more of a collection of CAPTCHA's. There is the Puzzle, The Smarties Chase (M&M's for American's) and my favorite the Horse Race. You don't get much more creative or human testing than this!

Go to their website and try the demos, even if you are not going to use them, they are still fun to play with!