It also doesn't have to spread it out over a particularly large area. If we are talking about the force of a punch from a good boxer, we only have to spread it over the area of the front of a boxing glove. That seems perfectly reasonable for a fabric layer soaked with a non-Newtonian fluid.

> You could sell me on Non-Newtonian-Kevlar though: Pliant to a slow crease, rock-hard with a sudden strike.

"Nanomachines, son. They harden in response to physical trauma."

According to that page, BAE systems et al were using kevlar soaked in a solution of polyethylene glycol and silica nanoparticles.

All readily available online, if you can afford something like $200 per 2ml of silica nanoparticles. It would be amazing to see one of the YouTube channels that has tried making their own, just make the real thing.

I imagine a suit made of dripping wet Kevlar wouldn't be too comfortable though. John Wick would experience some chafing.