U.K. company Hypertag is selling an innovate electronic billboard, one that encourages user interaction by sending messages to nearby mobile devices. As per the web site http://www.hypertag.com/, “It works by allowing infra-red mobile phones, and PDAs (e.g. Palm Pilots or Pocket PCs) to interact with a small electronic tag which is attached to the advert or sign. To use the system, you enable the infra-red port on your mobile phone and point lights. You wait a few seconds, and then a piece of content will be downloaded to your phone. This can be a word and number, a prompt to remind you of an important event, a picture, ring tone or game.” Hypertag has been available for a while now, but yesterday Netimperative reported that Bluetooth support is being added (see http://www.netimperative.com/2004/12/07/Interactive_posters_Bluetooth). Cool stuff.