CoolTown is the name given to a new technology currently under development by the clever people at Hewlett-Packard. It is essentially a means of associating messages with objects and, most interestingly, points in space. By assigning a GPS reference to the message (stored remotely on a web server) it can be delivered to any wireless devices within range of the reference. The server keeps track of the locations of clients, and sends out messages when appropriate. In simple terms this means messages can be left floating in the air for passers-by to read.
The project was initiated by HP researchers in Palo Alto, at first using barcodes rather than GPS locators. Later these gave way to radio waves emitted from beacons placed on objects, before the researchers hit upon idea of using GPS to remove the necessity of having physical markers for messages.
The nature of the technology would make leaving a floater no more complex than sending a text message, given a mobile phone, PDA or other communications device with a GPS reciever. I've been told that a Post-It note might also work, depending on the firmware.
HP open-sourced several components of the CoolTown under the GPL on July 23rd 2001, although it seems that these did not include the code necessary for GPS-based functions (perhaps as GPS signal coverage is still very patchy). The components released included the CoolBase Applicance Server, an object-oriented web application server; the intriguingly named Esquirt, apparently an API for the remote control of web devices through a PDA or mobile (we believe you, guys); and the Web Presence Manager, designed to pull together and create links between the various components of CoolTown.
It would of course be another step in the wrong direction as far as privacy is concerned (a central database of devices and where they are), but for anyone who has a mobile already (read: everyone) this is something of a moot point. The potential applications of the technology are numerous, anything from a note left for the milkman in the morning, providing warnings of potentially hazardous materials in laboratories and industrial evironments, or (in a similar vein) gleefully warning co-workers to steer clear of the toilets for a while. On a serious note, it alarms me to think what kind of havoc the trolls would wreak armed with the ability to piss people off in the real world, but hey! We'd be able to track them to their homes and hurl random abuse, and mud. I'm liking the sound of this thing more and more.
sources: New Scientist (www.newscientist.com, HP CoolTown Website (cooltown.hp.com), LinuxDevices.Com (www.linuxdevices.com).