Our device, trackr, is a beacon logging device. We one day hope to have trackr installed in all of the light posts on Notre Dame's campus.
Trackr detects Bluetooth LE beacons and logs their IDs along with a timestamp. These records can then be used to reconstruct the paths taken by the beacons' carriers.
With a range of 20m, a network of trackr instances can be used to pinpoint the exact locations of detected beacons.