Dean Drive

Mysterious invention of Norman Dean, touted as a reactionless space drive by John W. Campbell, Jr. in Analog. (It was basically a vibrating mass of unbalanced wheels which appeared to weigh less when turned on than when off. This was probably caused by a frequency dependence in the scales used to measure the weight.)

The Dean Drive didn't have the impact on Astounding's content that other pseudo-scientific nonsense like Psionics had, but was probably even more annoying to many since it was so obviously wrong.