Yeah, but not like I describe above. There were MANY installed around here in FL on the roofs of surrounding homes. My neighbor, yes, the one that did the instant electric heater, had one removed while doing her upgrade. Usually they would put and enclosure on the roof with glass panels, and run a series of piping (probably copper) back and forth inside the box. This was piped directly into the H/W tank, and a pump was used to circulate the water to the roof then back to the tank. It also had a timer on it so it would pump during the day only. I don't know if it used a thermostat of any kind in the system. It was so complicated that I've never met a single person that knew what they were or how to work them correctly!
Think of a solar pool heater, but more complicated. You might call this passive solar. Like I said earlier, all you really had to do down here was run your hot water piping through the attic and your cold under the slab. That way you get INSTANT hot water anywhere in the house! Attics here easily exceed 195 degrees almost year 'round.