During my time at Lancaster University, I was working on the Relate research project, which produces hard- and software for relative spatial positioning. My position was architectural design of the whole host software and development of some specific parts within the architecture.
Except dealing with the interface between the firmware of the USB dongles and the (Java) host software, my main research interest is spatial authentication. This means that devices should not be authenticated based on their name or the usual password or PIN (as for pairing Bluetooth devices), but based on their spatial relationship to each other. To put it simply, instead of entering the same PIN on both devices, the user would just select "that one over there" for the authentication process.
As a first demonstration application and proof-of-concept, IPSec (transport mode) connections can be created automatically between two devices after mutual authentication. An implementation is underway for Linux (with either KLIPS or the native IPSec stack and either the pluto IKE daemon from openswan/strongswan/freeswan or the racoon IKE daemon), MacOS/X Tiger (which uses the racoon IKE daemon) and Windows 2000/XP. For details on the authentication part of the relate project, please see my page on context authentication.