This was before we knew that the iPhone wasn't planned to ship with a native API (or that the eventual API and the phone itself would be so crippled), but for a brief, shining moment, I saw a world where everyone had a real computer in their pockets, always connected.
I really ought to go through my notes and implement some of those exuberant ideas for Android.
(To my delight, at least one of them has already been made: Google Sky Map. It's also smarter, as it uses GPS to determine where you are; my idea was to use the camera and image processing to recognize constellations).