Are disconnected tokens(1) as a 2-factor auth safe enough? Why not one of these on a thin enough tag to stick on your phone? Sounds like a very good solution f

Are disconnected tokens(1) as a 2-factor auth safe enough? Why not one of these on a thin enough tag to stick on your phone? Sounds like a very good solution for me. (1) http://en.wikipedia.org/wiki/Security_token#Disconnected_tokens http://en.wikipedia.org/wiki/Security_token#Disconnected_tok...