A wrist-watch on your hand? A ring on your finger? An earring in your ear? A ballpoint in your writing instrument?

I am a fan of wearable computers, but they are too easy to lose. And, I do not wish for Wireless communication to go through living matter, while the alternative (wires) is too cumbersome.

About bigger: a bicycle? a car? an airplane? a spaceship? a planet?

Good luck.