A team from the University of Ghent in Belgium is lacing the site of this year's Rock Werchter festival -- Brussel's equivalent of Woodstock '97 -- with Bluetooth scanners (36 total, they cover a range of 30 meters each). While you're rocking out to the likes of Bloc Party and Mastodon, the researchers will be tracking your every movement, whether it be to the mosh pit, the beer tent, or the Job Johnny. As you've probably assumed, the researchers are primarily looking for ways that retailers can monitor customer flow (read: sell you more crap) although there are certainly going to be results applicable to the world of law enforcement. Of course, this is Bluetooth: you always have the option of disabling it on your phone, and if you don't they'll only be able to discern your MAC address. Besides, if you're not doing anything illegal, you have nothing to fear from the surveillance state -- right? And if you are up to no good, well, that's why they invented the Dazer Lazer.