IMAGINE:

Worlds where all is transparent, where we move through matter easily,

and transmit nanomachines from one person to another.

Nanobots travel through our blood, semen, and other bodily fluids, and

once transmitted, they revert back to replicators.

Transmissibility of nanomachines in the body is a like bacterial infection,

using the same sorts of molecular cues as the immune system does.

Social problems are around interaction of people who have nanobots and those that don't.

Diamondoid-based medical nanorobotics offer substantial improvements in capabilities over natural biological systems.

Microbivores constitute a potentially large class of medical nanorobots.

The microbivore is an oblate spheroidal nanomedical device consisting of 610 billion precisely arranged structural atoms plus another ~150 billion mostly gas or water molecules when fully loaded.

The target bacterium is bound to the surface of the microbivore like a fly on flypaper.

A person can be injected with inorganic nanites (nanorobots) that would mulitiply gradually throughout the host's bloodstream and nervous system.

You must undergo strenuous mental training to correctly command the
nanotechnology within your own body. Otherwise you run the risk of having someone remotely control your embedded nanobots.