Exporting the past into the future:
Focusing on (a) nothing more granular than cities-as-place and days-as-time and (b) broadcasting future intention, we could find a valuable location-based service for a certain audience - surfacing coincidence for frequent travelers.
Point (b) though, still has me thinking that sharing your precise whereabouts - where you are right now, has limited value.
(via Short Sharp Science, via Nora3000)