Drexlerian nanotech

[Rynn]

Not neumanns or sporetech in general, but literally ones that fit on the head of a pin, that is, excessive miniaturization is not always good, even if the concept works. And yes, we are definitely talking past each other here.

Sure there are some extreme examples. If you fabricate a microscopic spore it's not going to be able to travel anywhere very fast or reliably. They're certainly not going to do anything in air other than be blown about, in a liquid medium they might swim at a similar speed to bacteria (about 50um/s which works out to 18cm/h) but any slight current or disturbance and they're knocked way off course. The only way around this transport issue is to use a tactic to get bigger; either by having a macroscale delivery system (like a robotic worm that releases microbots into the soil as it travels or a bird-bot that sprays them like crop dust) or building the microbots to attach to each other to become a large scale swarm.

On a final note, and building on what I said above - Bacteria, viruses, molds, and other such things are easily able to fit on the head of a pin, yet operate quite effectively 'in the wild' - in uncontrolled natural environments - not only replicating in vast numbers but sometimes having major effects on the environment, sometimes on a scale to dwarf anything achieved by humans. So your statement doesn't really seem to hold up when compared against the real world.

Fungus is a great example IMO and when I imagine this sort of growing/replicating smart matter I tend to think of it sharing similar characteristics. Take Armillaria ostoyae for example, it's a fungus that is one of the largest organisms in the world. All it takes is two spores (a male and a female) drifting on the wind and coming in contact on the ground to start growing. It pushes extensive mycelia through the soil with caps that regularly grow up through the surface (among other things to release new spores). When it grows up against a network of the same species they fuse, becoming one even bigger organism. This type of lifecycle seems very appropriate for smart matter, adding onto it organs that push through the surface to release roving bots.