Ok, I’m wearing my soothsayer hat and looking into my crystal ball:
I see a time when I can add a to-do item to my iPhone app that helps me organize my life (Things by the way) and I can define it so that it goes off when I enter a particular store or class of store.
For example: I always have a few to-dos related to the hardware store–but they’re never a priority. I’m forced to give them an arbitrary due date just to keep them in my mind. It never works that the arbitrary date is the day I walk into a hardware store!
Now, if there was some real smartness in my phone, it would know when I walked into a hardware store (Home Depot, Lowes, local hardware) and then beep and vibrate like crazy.
That would work for the grocery store or music store or… it would be cool and helpful.