[humidity sensors]

These are sensors that convert airborne moisture into electrical resistance (as found in Weather Service "radiosondes", balloon-suspended devices that measure atmospheric conditions and radio this information back to the ground tracking stations). This can give a breath control function to an instrument, raising a pitch, perhaps, as the sensor is blown upon.

There are many other components that can be wired into the path of the pairs of circuit-bending points, but the above will launch hundreds of possibilities as well as pave the way towards the understanding of wider concepts.

To quickly try different components between the discovered pairs of points, a modified test-lead system can be used. This consists of the two screwdrivers as before, two alligator clip test-leads instead of one, and the component to be tested (potentiometer, photo cell, LED, etc.). Clip a screwdriver at one end of each test lead. Between the empty ends of each test lead now clip the component to be tested. The screwdrivers again serve as probes with which to search the circuit, now sending the signal through the component clipped in the middle between the two leads.
 
Beyond direct electronic component wiring await other expansions...