1. In a portable electronic authorization device, a method for approving a transaction request originated from an electronic transaction system, comprising: receiving at said portable electronic authorization device first digital data, said first digital data representing said transaction request; and receiving from a user at said portable electronic authorization device a user input signal approving said transaction request; in response to receiving said user input, encrypting and transmitting a second digital data to said electronic transaction system, said second digital data being encrypted by hardware within said portable electronic authorization device and signifying said user's approval of said transaction request.