there actually was a component known by the name "flux capacitor". it was in either a Fluke or HP AC voltage standard manufactured in the 1970s. when i was in the PMEL/TMDE school at Lowry AFB, we had a Marine in our class that was a big fan of Back To The Future, and he also had a bad habit of falling asleep in class. when we were in class, after studying the particular voltage standard in question, the instructor, knowing the Marine had been asleep, asked him "what component controls the amplifier gain in the voltage standard?"... we were allowed to give hints for verbal quizzes, so everybody's yelling at him "1.21 GIGAWATTS!!!" and he still didn't get it.