... will confirm to your website that your new customer is a real individual. You protect your website against spam bots, prevents the same user re-filling web forms with different email addresses and at the same time you will get free Speedcoins which you later can convert to Bitcoins.
Live Demo: http://captcha.speedcoin.co/demo/example_form.php
Website: http://speedcoin.co/info/captcha/Speedcoin_Captcha.html
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