From Script-Tutorials.com there's a new post that wants to help you prevent one of the biggest menaces of the social online world - spam. Their solution uses the Akismet service to detect possible spam and notify you.
What is spam? – this is (usually) any message which not relevant to this page – usually just an advertisement of something (and even with a backward link to another site). Yes, you can put the first line of defense – a captcha, but I think spammers are also ready for this and find ways to avoid the CAPTCHA (or, they even can solve its by self). In today’s tutorial I’ll show you how to create a second line of defense against spam - using web services - for example akismet.
They include all the code you'll need to create a simple interface to the Akismet system with the help of this library that handles a lot of the connection and messaging for you. They apply it to a comment form and check the POSTed values against the Akismet spam checking. You can download the full package to get started immediately.