2013 Feb 7
Civil Rights CAPTCHA is unique in its approach at separating humans from bots, namely by using human emotion. This enables a simpler and more effective way of keeping sites spam free as well as taking a stand for human rights.
2012 Oct 6
2012 Sep 5
2011 Nov 3
2010 Nov 12
2009 Oct 20
Clickcha generates image based CAPTCHAs which require the user to click the image in a particular area to solve the puzzle. Clickcha is more secure than traditional text based CAPTCHAs which can be read via OCR software.
2009 Jun 25
2009 May 19
2008 Dec 8
2008 Oct 15
2008 Aug 30
2008 May 11
Asirra is a human interactive proof that asks users to identify photos of cats and dogs
2008 May 3
2008 May 3