Interesting and alternative uses for electronics components?

At my school, old wise men teach us all kinds of circuits and concepts, many using components in ways they were never intended for.

Thermal cutoff for a power supply uses normal 4007 diodes as temperature sensors.
Hollow pieces of stripped wiring plastic, heated slightly and used as heat shrink.
Reverse voltage of an LED used to detect daylight and guide a solar tracking motor.
21W light bulbs used as constant current sources because of their PTC characteristics.
Fuses made from single strands of copper, doubled up to handle greater current.

There must be more.

Using components and junk in ways they weren't intended opens up all kinds of possibilities for electronics people and students on tight budgets who don't have access to components and technology.

Are there other smart ways to put the characteristics of certain parts to smart use?

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klee27x7 years ago
Using an LED as a combo indicator/fuse, where the voltage drop and current range is acceptable. (Some cheapo batter chargers use this setup). Use a power MOSFET backwards as a power diode.
woody1237 years ago
exploding capacitors and punching holes in the light fittings!!!!!!!
use them for making art, for example;
make some component buddies or a necklace or something like that.
.Unknown.7 years ago
Battery as a bomb?
Some of the more interesting components I've pulled off circuit boards lately have been so eye-catching and beautiful in a particular way that I've started to set them aside for art projects instead of using them in electronics. By 'art projects', I guess I mostly mean as jewelry, but I can also see some of the components being used in miniature sculptures, scale models, mobiles, and elsewhere. I'm sure I will think of more uses for them as I work, but for now, I'm excited even though I only have maybe a dozen components that I thought were "pretty enough" to be used in my artwork. It will probably take me a long time to collect some really interesting things and rework them into 'objets d'art', but patience is key. When I do make something I'll be sure and upload an Instructable. :-D
Not sure these are solutions that were "never intended", they are very common in real world engineering, and derive directly from the characteristics of the devices.

The "light bulb trick" is or was often used to stabilse the output of oscillators.
A "fuse" IS a piece of copper wire !

I made a diode based temperature probe 35 years ago, when I was in school !
kelseymh7 years ago
This really deserves to be a Forum Topic rather than a "Question."  But its great either way!