My mom worked at GTE and when I went to college in 1997 she got us a WATS line so I could dial 1-800 to call home.<p>One of her jobs in the early 80s was to calculate the bills for WATS lines. There was a room full of mechanical counters, like odometers, that would increment while people were talking on their line. Every day she&#x27;d write down the new counts, subtract the previous day&#x27;s counts, and they&#x27;d bill the difference.