A while back I wondered how hard it would be to integrate two-factor authentication on a web site using Google's Authenticator app, since it uses open protocols

A while back I wondered how hard it would be to integrate two-factor authentication on a web site using Google's Authenticator app, since it uses open protocols and is available on all platforms. Turns out it's incredibly easy. Even made a demo: http://dendory.net/twofactors/ http://dendory.net/twofactors/