Bio-ID is actually even worse. Try a Retina scan after big night out, voice scan with a cough, finger scan after weekend warrior activities, etc. That simply fails. At least with with something like Authenta-key, because it's not just pass/fail, it can say "Well it's not a 100% match but the technique is close, hmm authorised so-and-so is online, lets get a challenge/response to vouch for them." The point is that depending on the security level the more stake holder humans in the loop, the harder it is to crack in.

Sorry, one more thing, this has the same easy of use and cost. In truth, as the user can choose which method(s) to use (another type of id check) it can be even easier. Imaging entering your user name and simply clicking a button to a tune or a certain timing to login? What about simply highlighting pieces of text in a paragraph? Low cost and ease of use is a win-win for Authenta-key. Just outsource your login to us. You can trust us right?