[Radiant] A captcha in Radiant?

[Jason Grimes]

Hi, I'm new to Radiant and like it a lot so far.  I would like to add a 
captcha to my site, has anyone done this yet?  I have been looking at 
Recaptcha ( http://recaptcha.net/ ) as a candidate to add to Radiant.  
The Recapcha site has two Ruby/Rails examples, one is a Rails plug-in, 
the other is a Ruby GEM and uses a Rails controller.  Which would be 
best to use for Radiant?  Could this be added to the mailer extension 
easily?  Thanks, any advice would be most appreciated. 

Jason