A consortium of Japanese firms including Hitachi and Matsushita Electric have started work on a system of wirelessly networked devices that watch your health as you go about your daily routine, with the intention of catching health problems in their early stages. Hitachi is making a mat that slides under your futon and measures pulse, breathing, and snoring while you're asleep; Matsushita is working on an unspecified device that allows the "easy measurement of the thickness of flab on your stomach and other areas" (a networked pair of calipers?), and Toto will bring out a toilet that measures salt and sugar levels in your urine as you pee. Fujitsu Prime Software Technologies contributes the communication format that will link everything up, and Mitsubishi Electric is working on a system that analyses the data. These should start appearing on the market around 2006, though by then the less squeamish of us could be implanting devices that do some of the same things.
(Lost the link for this one—the Nikkei Shimbun's site takes down articles faster than you can blink.)