[cookrn]

Not dial-up, but around 2004 you could find tutorials for how to unlock your (Verizon) Razr for USB access and OS X would recognize it as a PPP modem out of the box. I think an OTA update stopped it eventually.

[mikeash]

I wrote one of those! Fun to read through now, but highly obsolete. https://www.mikeash.com/alltel_internet.html