One of the most surprising applications for gas tubes in Miller's 01969 book, which I hadn't read before, is capacitive touch control of a 100mA solenoid. His Fig. 6–15 on p. 74 consists of four neon tubes (two T2–27–WR500, two 5AB-B), four resistors, two .001μF capacitors, a 4μF capacitor, a freewheeling diode for the solenoid, and the solenoid itself, and is powered by a 160VDC supply. When you touch the "on" or "off" touchplate, which is grounded through a 5.6MΩ resistor, your body capacitance momentarily provides a path for the 160V to ground before the touchplate capacitor charges up and blocks it. This kicks on the respective T2–27–WR500, which has a series 5AB-B to ground through a 6.8kΩ resistor shared between them. The two series pairs of tubes, connected on the high side through the other cap, form a flip-flop; the "off" pair has a 10kΩ resistor feeding it from the positive supply, while the "on" pair instead is supplied through the solenoid being controlled. When one pair turns on, the big cap couples a negative–going pulse to the other pair to turn it off.

12 low-precision components is pretty good for providing a flip-flop, high-voltage power switching†, capacitive touch sensing, and indicator lights. Miller seems to imply that such circuits were commonplace at the time.

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† I think the circuit is switching 3mA with 50 volts across the solenoid, so a respectable 150mW, even if the 5AB-B is only rated for 0.3mA. The T2-27-1WR500 is rated for 3mA. The 5AB-B has a maintaining voltage of 50–60V, the T2-27-1WR500 of 60–70V, so the voltage left across the series combination of the 10k high-side resistor and the 6.8k low-side resistor is something like 50V when the "off" side of the flip-flop is conducting, and 50V/16.8kΩ is just under 3mA. I assume the solenoid must have comparable resistance.