My phones each ring under two numbers: their "real" number and GV. I've got default ringtones that tell me whether its the end-point's "real" number or the GV number that's being rung.
If I hear the "real" number ring, it gets ignored (and then blacklisted and/or reported, since I've registered all my numbers, real or GV, with the do not call registry). If it goes through GV, then it's subject to the layers of rules I have there (screened unless explicitly excepted).
|Robo-Call (from Ars)|
Technology can be used to harass you, but it can also be used to shield you.