I'm thinking that I could disassemble things like keyboards,
mice, wireless toys, and instead of keys or motors
that move wheels or other mechanisms, use each action
as a value to send or receive data.

Probably even each channel (Left/Right) of normal
headphones and microphones could be amplified to
signal 1's and 0's.

Also probably photocells can be placed as an array in the screen
while driving an input/output program, apart enough as to
detect if the region that corresponds to it is bright or dark,
amplify enough, and use the screen as a means of sending
data to external devices.

The first intention is building an automated interface for
driving the address lines of old serial 2, 4, 8KB or so
ROMS to read back the 8 bits of data that they return.

So instead of moving address switches manually
and writing down the result bytes from LEDs at each
location, we will do the same automatically driving
the mentioned devices with software and hardware that
turns those outputs from the PC to 1's or 0's to
establish the state, and probably the typed characters
from the disassembled keyboard (by the device)
to be used for the returned data with a text editor
or key logger focused to capture the data automatically.