I've seen this called "Honeypot CAPTCHA"[0]. I'd say it's good for 90% of sites, up until the point where spammers or fraudsters start targeting you specificall

I've seen this called "Honeypot CAPTCHA"[0]. I'd say it's good for 90% of sites, up until the point where spammers or fraudsters start targeting you specifically. [0]: http://haacked.com/archive/2007/09/11/honeypot-captcha.aspx/ http://haacked.com/archive/2007/09/11/honeypot-captcha.aspx/