Spam?

[Alrin]

If you saw the Human Computation speak, you would pick up that certain companies (say, porn sites etc) are able to feed a forum registration captcha into their websites to have their browsing users solve the captcha for them, live. Thus, giving them a filled form (hidden from the user, they only see the actual captcha and eagerly fill it in to see the next pair of hooters) that they are able to (?) process and get another spam account.
Atleast thats the gist of what the speaker hinted at when he mentioned creative ways to circumvent computer automated problems that cannot be solved my machines.