From https://news.ycombinator.com/item?id=40759133 :

> In addition to nanolithography and nanoassembly, there is 3d printing with graphene.

And conductive aerogels, and carbon nanotube production at scale

From https://news.ycombinator.com/item?id=41210021 :

> There's already conductive graphene 3d printing filament (and far less conductive graphene). Looks like 0.8ohm*cm may be the least resistive graphene filament available: https://www.google.com/search?q=graphene+3d+printer+filament...

> Are there yet CNT or Twisted SWCNT Twisted Single-Walled Carbon Nanotube substitutes for copper wiring?

Aren't there carbon nanotube superconducting cables?

Instead of copper, there are plastic waveguides