Somehow I guessed that you were one of the original 'Riders of the 4 Course Radio Range' listening for As and Ns, Chuck!
Did you really 'keep to the right' in IMC to avoid collisions before the days of IFR semi-circs?
I use GPS as a back-up as ours aren't IFR-approved. Plus we've had our share of RAIM warnings.
It'd be intruiging to know how many NDB approches really were within 5 deg of the deefining course when flown by little spamcans with suction driven DIs set against a swinging liquid compass - and with only an RBI.....
In my old 'day job' aircraft, we had Y-code GPS blended with laser INS. If you could persuade the lazy $od to do so, you could get the navigator to set it up with the NDB approach course as a course to steer to the beacon position, and then, in some aircraft, display it on the HSI CDI bar. Only as a back-up, of course - we still had to use the RMI for approach guidance. But it was reassuring to see the flickering, twitching RMI backed up with nice, steady 'on-course' CDI indications.....