Mac serial port, now you see it, now you don't!

ifugaopapercraft:
The most exasperating problem with Arduino has been the availability of serial ports, or rather, the lack of serial ports.

I have never had any such problem with either FTDI-based (Pro Mini) or ATmega8u2-based boards (Uno/Mega).

ifugaopapercraft:
Tried previous Arduino versions with the same result.

The IDE has nothing to do with the serial ports appearing. That's between OSX and the device being attached.

ifugaopapercraft:
Mega and older boards with Uno chips will show appropriate ports.

Look at the common denominators. Either it is the boards (they aren't from eBay, right?), the cable, or the driver for the FTDI chip on the boards.