Musical Prototypes Via Ektopia:

[Notewriter]
[Old School Portable Beat Machine]
For the Real Deal, some cool online galleries:
--> Audio Playground Keyboard Museum
--> IEEE Virtual Museum - Songs In The Key of E
--> Raymond Scott Studio Pictures
--> Oddmusic Gallery
This is not to say that I personally have any idea how these work or what makes them historically/conceptually special. They just look very cool.

[Fairlight]
[Stylophone]

[Wall of Sound]
[classic theremin]

[Riday T91]