minotaur - Rid the internet of text CAPTCHAs!
Download the plugin and extract the folder contained within.
Upload or copy the folder to your /wp-content/plugins directory.
Visit http://min.otaur.com/ and sign up for a FREE minotaur key
Activate the plugin through the 'Plugins' menu in WordPress
Go to the 'Settings' menu in WordPress and set your minotaur host private key