I've been cheating--on my day job. I've been moonlighting as a tour writer for a small publishing startup called Rama. They are in the business of producing walking tours that can be downloaded onto your iPhone (for now, later they will probably expand). These aren't just your average, ho-hum "and this building here once housed seventy-five cats" sort of tours, though: they take you on a historical reminiscence about the place, with photographs of what once was.
If you're interested in writing a tour, please please PLEASE get back to me. Compensation is financial--50% of the price, after Apple takes their cut, and you get to say how much it will cost.