Tangential to the above question. This is for a novel about a somewhat near future. The conceit is that very advanced nanites, plus computers that are able to read our minds, equals something like sorcery. You still have to create or find schematics, but you can essentially think of a thing and the nanites will make it real. There are obviously limitations. Nanites could only create energy indirectly, for example, and couldn't give you powers that defied the laws of physics. But they could create all new organisms or make things that would be too intricate for conventional manufacturing. These are nanites at the viral or bacterial scale, which can change one molecule into another molecule by manipulating the atomic bonds. Our bodies do it, so I'm assuming we can make nanites that do it.
The way I imagine it now, people customize their environment and their own bodies a lot, as quickly as their moods change. People are effectively immortal, can teleport themselves anywhere with WiFi signal, and change forms into anything that obeys the laws of physics and preserves their brain and its functions. As it stands now, transforming from a standard human to something like a dragon would take just a few seconds, thanks to the ubiquity of the nanites. But the more research I do, the more I'm convinced that speed is not actually possible. I've solved the power and communication problems, but transport and movement of the nanites is a more fundamental task that no one seems to know the upper limits of for sure.
Obviously, it's a story and things don't have to be completely realistic, but I'm trying to make it at least plausible. The construction process has to follow the laws of physics that we know are definitely true. Or at least, stay close to the edge of what's possible. I need to know how the construction of a whole organism would be broken down, and especially, how long it would take in an environment completely saturated with nanites.