12. A computer-readable medium whose executable contents when executed by a processor cause a mobile device to perform a method for initiating a purchase, the method comprising: capturing a text sequence from a rendered document using the mobile device; identifying by the mobile device a reference to a distinguished product within the contents of the captured text sequence; in response to the identifying, presenting on a display of the mobile device to the user an opportunity to order the distinguished product; and when the user accepts the opportunity to order the distinguished product, ordering the distinguished product on behalf of the user.
12. A computer-readable medium whose executable contents when executed by a processor cause a mobile device to perform a method for initiating a purchase, the method comprising: capturing a text sequence from a rendered document using the mobile device; identifying by the mobile device a reference to a distinguished product within the contents of the captured text sequence; in response to the identifying, presenting on a display of the mobile device to the user an opportunity to order the distinguished product; and when the user accepts the opportunity to order the distinguished product, ordering the distinguished product on behalf of the user. 15. The computer-readable medium of claim 12 , wherein capturing the text sequence from the rendered document using the mobile device includes taking an image of a portion of the rendered document using a camera of the mobile device.