This company sells conductive fabrics, woven not out of fiber but very, very fine wires. They seem ideal for sourcing primary components for building shielding - say, you're constructing an RF testing facility and you want to minimize leakage (or intrusive external signals). Or you're building yourself a Faraday cage for some reason.
Send them a graphic of some kind and they'll do custom fabric of it for you. No minimum order, they even sell test swatches.