Yeah, even recaptcha is broken. A new board I helped set up at my company got some spam before even being publicly announced!
On my blog I generate two random sequences of characters and tell the user to join them together without a space. This seems to have worked really well. (Though in the past I've also had static strings like "join 'bow' and 'ser' together" or "join 'doc' and 'tor' together".) I used to have the addition challenge like the GP but it was broken. My comment form was slammed with hits, so I rate-limited attempts, but a few still got through (since it's actually not a big set of responses to go through and you can defeat rate limits). That's when I implemented my string scheme and changed the comment form submission url (which only lives in Javascript now), haven't had a spammer get through yet.
On another forum I used to moderate (I think it was an Invision Powerboards one) I fixed it with a second field asking something like "What makes things fall down? gravity or noodles?" And if they entered gravity it would let them register. It lasted a few years, then a few randomly got in but by that time the forum had died.
Comments
Yeah, even recaptcha is broken. A new board I helped set up at my company got some spam before even being publicly announced!
On my blog I generate two random sequences of characters and tell the user to join them together without a space. This seems to have worked really well. (Though in the past I've also had static strings like "join 'bow' and 'ser' together" or "join 'doc' and 'tor' together".) I used to have the addition challenge like the GP but it was broken. My comment form was slammed with hits, so I rate-limited attempts, but a few still got through (since it's actually not a big set of responses to go through and you can defeat rate limits). That's when I implemented my string scheme and changed the comment form submission url (which only lives in Javascript now), haven't had a spammer get through yet.
On another forum I used to moderate (I think it was an Invision Powerboards one) I fixed it with a second field asking something like "What makes things fall down? gravity or noodles?" And if they entered gravity it would let them register. It lasted a few years, then a few randomly got in but by that time the forum had died.