Simplicity...

I am a self confessed gadget geek. I do love a new gizmo. I also have a very inquisitive mind and usually want to have at least a basic understanding of how something works without needing to know the intricacies of every wee detail of each diode and resistor.

That said I do also really like when something is so simple and low tech that you can see exactly what it does and how it does.

Beautiful simplicity...

Can you guess the tune this plays?