Brian De Palma w/ Nancy Allen was my first thought -

She has little electric stingers she can throw - she hurls one at Winter Soldier during their fight. She activates one on herself and as well as knocking her out, it temporarily shorts out Pierce's device so he can't kill her.

Well, this Natasha (as opposed to the comics) probably served in one of the later offshoots, but the problem there is, you say those initials, half the audience won't get it. You say K-G-B, they get it. Accurate, no. Better for the movie, yes.

I don't think there's anything particularly "fascist" about Fury shooting Pierce, when at that moment Pierce is a millisecond away from burning a hole in Natasha. Once she stings herself out and temporarily kills the device, he reboots it on his phone straight away and Fury tags him *right* as it's ready to kill her…