The odd alternatives to passwords

With hack after hack hitting the headlines, existing authentication systems are clearly in trouble - but some of the proposed solutions are nothing short of wacky. As hackers continue to successfully steal data and dump it online, and manage to crack even the toughest bot-prevention tools, it's clear something needs to be done to boost the traditional tools of user authentication, such as passwords and CAPTCHAs. Some of the proposed alternatives have yet to make it big - and it's no surprise why that is. Here are the weirdest and wackiest ideas so far.