For this we first need to have something like a dyndns and/or reverse SSH tunnels...

From there, we need to figure out how to extract all the GPS / Pictures / Fingerprint (haha) and pop d-bus messages on activity.

Al this shouldn't be too hard to setup but still need quite some work to make it usable and not break anything.

Also, i would advise against saying you are about to destroy the phone as the thief might be quick and turn it off... We'd be better erasing it, setting up the boot menu and try to put there a message saying where to write to send it back or some such :-)