I'm thinking about a device in a gut with this i-beam stuck into an enterocyte. This device would have to read the change in color and then send the info back outside of the animal body to the computer. The device might be on the order of 100 micrometers? Or, that small device can be placed also in a connective tissue of skin and have this i-beam stuck in a fibroblast.

I hope I live to see mature nanotech. All these developments are exciting and accelerating, but we're still just at the beginning of the coming revolution. Nanotechnology will change civilization more than agricultural, industrial, and the information revolutions combined.

I hope to live to see the Disco era make a comeback, then I can blink to the music on the dance floor.