A few weeks back, the gaffer blogged about USBCell's - essentially AA batteries that are charged by plugging them into a USB slot. Now Steve has gone and ordered some, and I believe they arrived a while back, but, what do I say to that? Well, I take your USBCell, and I raise you, with the AngelKey!
Basically, its a USB key that stores your medical data, that you supply, such as blood type, blood pressure, any medication you're currently taking and more. I guess, like the Techie Diva says, it assumes that the paramedics, when they are rushing to save your life, have their laptops with them, can quickly start-up (from hibernation), and they have a spare USB slot! (not using too many ReadyBoost devices ;-))
I believe it's only in the U.S at the moment, so all us Brit's will just have to wait!
You could always order one of these as a stop-gap. Not quite as useful, but everyone needs a USB duck-vacuum right?
Now, who's my Secret Santa....?