Jake, I'm on your side. I hate putting the load onto the user. Captchas fail when it comes to users with disabilities. But like Mike says, Spammers are running bots, but not "using" your site. I find a nice little trick of putting a <input type=hidden> field in and then using a small piece of JavaScript to set the value to the DocID of the parent later down the page works. If the submission doesn't match field vs parentID then they haven't used your webpage, and you can effectively block the message.
Now people will complain about how it discriminates against users who aren't running Javascript. But seriously folks, who doesn't have JavaScript enabled or is using ancient (seriously ancient) browsers?
Jake, I'm on your side. I hate putting the load onto the user. Captchas fail when it comes to users with disabilities. But like Mike says, Spammers are running bots, but not "using" your site. I find a nice little trick of putting a <input type=hidden> field in and then using a small piece of JavaScript to set the value to the DocID of the parent later down the page works. If the submission doesn't match field vs parentID then they haven't used your webpage, and you can effectively block the message.
Now people will complain about how it discriminates against users who aren't running Javascript. But seriously folks, who doesn't have JavaScript enabled or is using ancient (seriously ancient) browsers?