The easiest way to implement an unusual Captcha with images instead of text and drag & drop capabilities.
4.0: Now with Accessibility support!! Retina-ready!! Added support for jQuery 1.8 and jQuery UI 1.9, new images and refactored code.
3.0: Added support for jQuery 1.7, new images and improved code readability.
2.1: Now supporting drag out and in other items, one at a time!
2.0: Now supporting Mobile Devices (through tap/touch)!

We have it prepared to be setup in an Horizontal or Vertical way (css changes and the number of images showing). Type 0 is Horizontal and 1 is Vertical. By default, Horizontal is applied, so if you want to show it vertically, you can use:
printCaptcha('frm_sample',1);
For detailed instructions, click here.
Captcha is a great thing, it makes it more difficult (hopefully impossible) for bots to submit forms "blindly", creating/sending junk to mails/databases.
However, through time, we've become more and more aware it doesn't work as expected. It difficults communication, and as such, people make mistakes often in the common Captcha forms, making it sometimes a reason for giving up filling a form (specially when the form is big and it doesn't refill the sent information).
So, we thought: "wouldn't it be great to find a way to make a Captcha work better for humans and still be impossible to be submitted automatically by bots?"
We found a great concept for this answer at Ajax Fancy Captcha - jQuery Plugin, but also found in it a few bugs and easy ways for bots to "learn" how to bypass it. As there was nothing really good and innovative as we wanted it, we built our own!
You can find some more info here: http://visualcaptcha.net/
Very impressive easy to expand and implement.
Very nice and very simple to use... thumbs up! Nice Job!
Well done and original work.
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