A free, independent, and open source set of curricula for learning languages.

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.

A list of education resources licensed under the Creative Commons for all grades and levels of advancement. Among the resources listed is MIT's OpenCourseware, the Khan Academy, and the CK-12 Foundation.