If we don't make a system where that data can be bought and sold based on the preferences of the person being data mined, then privacy will be blown out the window in just 30 years. There will be no reason to introduce yourself to people, all they have to do is access your logs.
All it takes is one person who knows what they're doing to find out a -LOT- about you.
Then, when I want to query the data, a client-side Javascript app can display it on a timeline on a map. You plug your encryption key into this client-side app.
It would also be cool to create a host-proof method for indexing the location itself, so I could ask the service for all of the logs within a certain radius of a location. Not sure how to do this securely yet, though.
Passively monitors your location every 10 minutes, collates, and then lets you view graphs etc. from within the app. Information is not shared with anyone - it's designed purely for an individual user.
I realize this is a self-serving post, but thought it might be relevant. The app just got dropped to $0.99.