I was thinking the other day, what I want is geolocation push notifications to my iPhone. For a trivial example, I have been meaning to ask my coffee shop if I could have some of their empty ice cream tubs. Every day I pull up at their drive through caffeine-deprived, pick up my coffee... and forget to ask.

Sure would be great if, while I was sitting there waiting for my drink, my phone blipped "Ask them about the damn tubs already" :-)

The hard part is setting up the notification in the first place. You might be able to wire up something to Google Maps that lets you put pins down that can be queried by your server.

Or something like that, anyway. Sounds like a neat idea :)