Well it's true the way I've implemented jcatpcha comes with inaccessibility issues, although JCaptcha and other CATPCHA systems have the "play sound" feature, although I haven't looked much into it. Maybe on a next version!

A good example of a captcha system breaking the inaccessibility barriers is, for example, the {link:google's sitemap register page|url=https://www.google.com/accounts/NewAccount?service=sitemaps&followup=http://www.google.com%2Fwebmasters%2Ftools%2Fsiteoverview%3Fhl%3Den&continue=http://www.google.com%2Fwebmasters%2Ftools%2Fsiteoverview%3Fhl%3Den&hl=en} where you also can play sound of the letters.

I'm glad you like the design, I think I'm addicted to it! Can't stop looking ~~laugh~~