Back in the day,
FroshPhysics lab involved something called the Damped Driven Harmonic Oscillator. (Or, as
ProfessorSaeta once referred to it, the "Damned Driven Harmonic Oscillator", a sentiment echoed by many of the students.) This involved watching a little shaft push in and out of a little cylinder of water (or some other damping fluid). In and out.... in and out....
Also part of one of
AlexBobbs's anagrams "(To the)
SexLab, Bob!"