@RichTW, no, we don't have text-to-speech functionality on the captcha ... getting that to work reliably across all potential platforms (*shudder* RISC OS!) is unfeasible.
@DavidB, as Rich says - the CAPTCHA has to be challenging to filter the automated spambot registrations. Unfortunately, even the complex one we currently use has recently been breached on one of the forums I manage, so that should give you some impression of the scale of the problem.
I am trialling the removal of the image captcha, using text question only. If it holds, I may move the Retro Software forum over to that in the future.
As Rich has also pointed out, tho - you only have to register once, so I don't see it as a huge inconvenience. For anyone who simply can't manage it, there's also the option of emailing
contact@retrosoftware.co.uk to ask for help.
Sam.