Now, where did I put that deodorant?A sweaty gym workout is not only good for your health - it could also energise your phone.
A tattoo that produces power from perspiration has been unveiled at the American Chemical Society meeting.
The biobattery is fuelled by lactate - which is naturally present in sweat after vigorous exercise.
It could soon power heart monitors, digital watches and eventually even smartphones, say scientists in California.
Biobatteries
Moderator: Peak Moderation
Biobatteries
http://www.bbc.co.uk/news/science-environment-28791496