Proton, the Swiss company that develops privacy-focused online services such as email, has developed its very own CAPTCHA service to help discern between genuine login attempts and bots -- and it touts the new system as the world's first CAPTCHA that is "censorship resistant." "As we investigated available CAPTCHA options, we weren’t satisfied, so we decided to develop our own," Eamonn Maguire, a former Facebook engineer who now heads up Proton's machine learning team, wrote in a blog post.