From here:
Thanks for the pingback. It was appreciated and I have responded in turn! I agree that reCAPTCHA is a pretty cool web application and it certainly beats all of the current spam tools except for maybe Akismet. My only gripe with them as I mentioned is that I would need an enterprise key which I don’t really want to buy obviously. Therefore in terms of any plugins with captcha (really the only way to go) is with the reCAPTCHA plugin. Highly Recommended! 5 Stars!
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Hi, just to share with you that this plugin at
http://wordpress.org/extend/plugins/wp-spamfree/
works very very well in my single WP and WPMU installs.
Cheers.
Thanks for that. I might have to look into it. Right now, I’m using Bad Behavior and it’s working decently well.