As a teenager, I very much enjoyed the hands-on aspect of high school physics. I was especially fascinated by the principles of light, lasers, and the large Fresnel lens. It was hard for me, however, to concentrate enough on the rote memorization aspect of the class, and I ended up taking it more than once, ultimately passing just by the skin of my teeth.
I eventually went on to a career as a Registered Nurse, and found myself working with a large, multi-person hyperbaric chamber, where patients are exposed to a pressurized environment and given highly concentrated oxygen to breathe (when compressed to three times normal atmospheric pressure, one breath of 100% oxygen contains as many oxygen molecules as three breaths of oxygen at normal pressure).
Part of my job became teaching the principles of hyperbaric medicine to other RNs and hyperbaric technicians. I included discussions of Boyle's Law, Dalton's Law, Henry's Law, Charles' Law, and Gay-Lussac's Law. In my powerpoint presentation, the title of this section of the teaching is:
"Physics 101: All the things you ignored in high school, but now, through some cruel twist of fate, have again become pertinent to your life"

Thingy for tuning piano strings?

Part of a set of handcuffs.

A manual drill

"I can't believe I slept with an otter..."

By 2007, global warming had become so bad that even the polar bears themselves had begun to melt...

A surgical device for retracting skin?

It's the throttle gauge for a boat. You set the percent of the engine power you want to use.

Early model handcuffs?

Looks upside-down to me. Is it an armrest from a chair? Part of a desk perhaps?