I look at biometrics as just another category of of the 2nd factor: things you have.<p>You have your fingers.  You have your eyes.<p>In fiction and movies, these things that you have which could be taken from you (your fingers severed, your eyes plucked out) and used for getting past biometric scanners.<p>In real life there are easier, stealthier, and less gruesome methods for getting those things:  just copy them.  (gummy bear fingerprints, anyone? [1][2][3])<p>[1] - <a href="http:&#x2F;&#x2F;www.theregister.co.uk&#x2F;2002&#x2F;05&#x2F;16&#x2F;gummi_bears_defeat_fingerprint_sensors&#x2F;" rel="nofollow">http:&#x2F;&#x2F;www.theregister.co.uk&#x2F;2002&#x2F;05&#x2F;16&#x2F;gummi_bears_defeat_f...</a><p>[2] - <a href="http:&#x2F;&#x2F;www.cryptome.org&#x2F;gummy.htm" rel="nofollow">http:&#x2F;&#x2F;www.cryptome.org&#x2F;gummy.htm</a><p>[3] - <a href="http:&#x2F;&#x2F;www.it.slashdot.org&#x2F;story&#x2F;10&#x2F;10&#x2F;28&#x2F;0124242&#x2F;aussie-kids-foil-finger-scanner-with-gummi-bears" rel="nofollow">http:&#x2F;&#x2F;www.it.slashdot.org&#x2F;story&#x2F;10&#x2F;10&#x2F;28&#x2F;0124242&#x2F;aussie-kid...</a>