The thing is (at the risk of sounding like a broken record) if you just charge every user for a sign up, then you never need to worry about captchas. Because even if a SPAM bot signs up, well you get paid and that’s not a sustainable model for spammers.
I pay the small monthly fee for access to Ben’s blog and it’s a great experience. Without ads or sponsorship, all of Ben’s content is just for me: the reader.
***edit a day later**
Oh yeah, I should probably say something about how I feel about Captchas. Just like attempting to curb piracy, all they do is piss off legitimate users. The robots will get into your system no matter what. People will pirate your apps no matter what. But I don’t believe in comments or any part of the internet that gives you anonymity so what do I know