I had a somewhat 'similar' idea last year. Pick a place in the world and every morning (or once a week) receive a picture of the sunrise there. The time of day can be altered and the location within the city can be altered. Would be cool for people who miss home or who wonder what it'd be like to wake up elsewhere.

On a side note, not sure if this exists but what about a desktop picture app that changes your desktop daily based on your settings/preferences?