[OT] How to get calling number when CallerID reports "unknown"

[Michael ODonnell]

IIRC there have been complaints that some of the
roll-your-own telephony software (such as was being
discussed in recent weeks/months on this list)
made it easy to peek at the call-setup and other
telephony metadata normally unavailable to civilians.
I think I've heard that some folks were unhappy that
CallerID-blocking could be defeated this way since
that can be very bad news if you're (say) an abused
spouse phoning from a safe-house...

Also, last time I had to get the phone company to
help me deal with some harrassing calls the first
thing they insisted I do was file a formal complaint
with the cops so that I could supply them with the
case number.