According to The Register, Philips is taking wearable computing one step further with underpants ("pants", "briefs" or "smalls" in British English) that monitor the wearer's blood pressure.
The hi-tech undies have sensors sewn into the waistband that measure the wearer's pulse wave velocity - the rate at which pulses of blood stream through a person's circulatory system. By measuring the time it takes for one pulse to pass between two sensors, the smalls will be able to calculate the wearer's blood pressure.
(The photo is from the Philips patent application.)
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