Prevent SPAM with Akismet – Magento Connect
Lately there is more and more spam on the web. Especially WordPress is notorious for getting a lot of comment spam, but nowadays Magento also suffers from review and contact form spam.
Luckily there is a free extension that enables Captcha and Aksimet protection for product reviews and contact forms in Magento.
I recently came across it and thought it would be a good share: