Researchers over at the Kaiteki Institute in Japan now say you can keep track of your heart rate with a cheap pair of in-ear headphones.

They used a technique that measures the pressure changes inside the ear canal caused by the eardrum being vibrated by moving arteries and were able to accurately measure a subject's heart rate with nothing more than custom software and a cheap $8 pair of earbuds.

Will this turn in to an app?  [Tech-on!]