Kinda.

Something that stops interaction between those two electrodes(no plasma emitted in that path, no charge)

No, because:

Imagine you have an triangle, with electrodes A, B and C. You want A and B to transmit charges, A and C can too, but you don't want C transmit or receive charges to B. My idea is, you place a material somewhere in the direct line between C and B, and it stops interaction between C and B(no plasma emitted, nor charge is transmitted).

Could be useful on wireless data, and will add another to-do stuff for people who makes processors and that kind of stuff

I have some ideas too...
Some biologic elements, like plant. Maybe alcohol (flamable, lighter than water), and something like plant+photon=glucose and glucose+pressure/heat=alcohol.

does anyone else read ETRD as e-trade?

@fabrizziop
anyway, why not make it so that after placing a point of ETRD you draw a line to another ETRD to connect the two. you could connect A and B, and B and C, but because not connecting A and C those two would not connect.

I was thinking that dry ice would be a cool element

@egaryyo: That also works ;)