When 3D Printing begins using a nanotube carbon-fiber medium, we will see a huge change in structure.
Woven loosely, the cloth still fine, will lay and shimmer like silk, (but ring like a huge gong when stopping a .50 caliber rifle round).
Stacked tightly, the thickness of light cardboard will hold spaceship hull structure and withstand debris impact thousands of times what current shell materials withstand.
None of this even begins to tread the paths that interwoven linked-molecule computers will be able to accomplish.
Complete invisibility, through ‘active blending’ with surroundings wherever you go.
Active-armor clothing for combat situations, uniforms themselves are armor, and a complete file history of the soldier wearing it.
Vehicles capable of safely transporting hundreds of times their own weight.
Air and space travel in vehicles who’s structures weigh less than a 1/100th of their predecessors.
Components that never wear out.
Earthquake-proof buildings that if shaken off, can be lifted and set back on repaired pad.
Buildings that make drive-by shootings a futile endeavor, and place the shooter in greater risk of being hit by ricochet, than anyone inside being bothered by someone having ‘issues’ with them.
Personal submarines that cruise the ocean depths.
Skyscrapers that require cabin pressurization.