CAPTCHA, or “Completely Automated Public Turing test to tell Computers and Humans Apart” (Wikipedia definition), is the de-facto standard of authenticating humans and telling them apart from machines on the Internet. However, some sites go way too far with CAPTCHAs, as these funny CAPTCHA examples show. (via Digg)
Amit Schreiber's Blog | הבלוג של עמית שרייבר