[tempestn]

I recall using this occasionally in the 90s even. There was also a period where I would regularly "one ring" my parents as code to call me back. IIRC that was because my cell plan had unlimited (or at least more) incoming minutes.

[account42]

It will never stop being weird to me how US mobile plans make (or made) you pay for incoming calls and texts.

[dizhn]

Collect calls would have been a thing until cell phones got very common because you had to use pay phones when you were outside and you somehow never had quarters.