A short review of some of the leading comments spam prevention techniques, from Captcha to Akismet and the Project Honey Pot.

As more bots and hackers find their ways to bypass Capchas one must ask himself: Wouldn’t it be better to set a limit to Captcha wrong attempts?

Captcha service protects websites and navigators from robot spammers which spider the web to accumulate emails or registration to sites like forums and blogs…

Captcha is known for being a spam prevention effective solution in regards to all forms of spam that can be done by bots. The reason for that lies in the fact that Captcha is a test that validates web users as human beings, just as the name implies: CAPTCHA = Completely Automated Public Turing test [...]

Captcha is known for its efficiency in ensuring proper use of websites and online application by validating that the user is human and not a bot or some other automatic machine.
This article lists some of the security applications / uses of CAPTCHA:
Comments spam prevention
Comments spam is used in blogs and forums mostly for raising search [...]