Quote from: Lethos on December 05, 2012, 09:15:28 PM

In my experience with Wiki's most captcha based additional verification before account creation doesn't slow it down much.
They guess those rather two well.
What slows it down the most is simple but random question of your own choice.
Having something non standard, means the bot just won't be able to guess it, but a human will know the answer.
The donation method is also great, just take a bit more to implement. It would once done before more likely to beat the bots and spammers.

Correct captcha relay is about $1.60 for a thousand solutions. Doesnt slow down spammers. What will stop spammer dead in its tracks is subject-matter related question on signup. Like "How many bitcoins will there ever be?" ... answer 21000000 ... or fill in the blank "Satoshi ______" answer Nakamoto ... etc.

Quote from: J-Norm on December 05, 2012, 09:23:27 PM

A clever spammer could create a website that relays any sort of captcha challenge to users who are willing to solve them for .01BTC each. It has been done before, but using porn for a reward instead of bitcoins. Same principal.

typers in kazakhstan or indonesia are happy to do it for USD$0.80 per 1000 solutions = 0.061 Bitcoins for 1000 solutions = thats like 0.00061 bitcoins per solution. Thats the supply side for the typing workers. The demand side of companies that sell the bulk solutions (imagetypers, deathbycaptcha, decaptcher, etc. etc.) can charge $1.6 per 1000 .. i tihnk there is also a middleman in there somewhere. anyway captcha solving is a perfect business to disintermediate with bitcoins if workers would accept them and buyers would pay with them lol.