If you've ever run down your iPod battery because you took our your earbuds but didn't turn it off all the way before dropping it in your pocket or purse, designers Sunmi Hwang, Hyunjoo-Lee & Jiwon-Seok have a solution with their Airtube concept. These are earbuds that automatically shut off your MP3 player when you remove the earbuds. If you aren't listening, it's not playing.
According to Yanko Design, "The Air Tube Earphones are fitted with a pressure sensor in the earbuds. This helps the earphones instinctively understand if the user is still wearing his earphones or has removed them." And if you have removed them, you'll know your battery is not going to waste.
I've definitely been in the situation before where I've hastily removed my earbuds to talk with someone and never put them back in, which means hours later I've discovered that my music is still playing and my battery is low. I'd love earbuds that act as an on-off switch. If these could be a reality, with an added embodied energy footprint from manufacturing that justifies their energy saving capabilities overall, then I'm all for them!