After dealing with repeated robotic assaults trying to register thousands of spam accounts, we've instituted a "riddle" check that asks a (very) simple question that you provide a one word answer to.
For example: "What is the color of the Sun?"
You would type: yellow
Hopefully this will be both more effective and easier on the eyes than the painful CAPTCHA image system.
If you attempt to register but have issues, please email: firstname.lastname@example.org with your details and I will help untangle any situation.