[vesrah]

While not directly related to your question, back in the day (like 2002-2003 or something) Jagex added fatigue in attempt to combat botting. The solution was an addition to the botting client that encoded the captcha image and dumped it into an IRC channel. There was a second client called Sleepwalker, iirc, that read the encoded captcha images from IRC, a user would type the captcha text, and the client would put the decoded text back into the IRC channel for the bot client to pick up and use. There was basically a credit system so you had to spend some time typing others captchas so yours would be decoded by others.