This C/Net article describes how a group of MIT grads are using inductance instead of radio waves to form a personal area network. Let's forget for a moment that this will probably erase most hard drives, but it does have some interesting applications.

I've always wanted a sort of "charging pad". This would be a flat pad you plug into the wall. You drop all of your gear on it: PDA, cell phone, etc, and they're all charged through magnetic induction. The MIT folks have taken this a bit father by transfering data instead of power. Combine these two and you have a pretty strong bit of technology: I can sync my PDA and charge it just by dropping it on a pad. I can take my cell phone and sync it to my PDA contacts by getting them close to one another, but when I place my cell phone on the pad it can also get a high speed internet connection to upload all of the pictures I've taken to my blog.

You could even generalize the power / communication interface a bit more. With a standard power / com interface t would be possible to use my PDA's power to drive my cell phone if I need to make an emergency call and my phone battery has died. If this technology was also in my car, my PDA could be streaming audio to my stereo and getting a trickle charge at the same time from the car battery. That's cool.