Wearable computing. Researchers wearing devices that are linked to a portable computer. Informa- tion is relayed to them by displays on the inside of the Private Eye display unit which can be mounted on spectacles or held to the eye. Data is entered into the computer through hand-held Twiddler devices which combine the functions of a keyboard & computer mouse. The researcher on the left has a chest-mounted camera which the computer can use to recognise people she meets and then automatically display information about them. The lightweight computer and power supply are carried on belts or in a bag. Photographed at the Massachusetts Institute of Technology, USA.