That you otherwise aren’t using, because you know, FaceBook…
Seriously though Duet Display actually works surprisingly well with both Windows and Macs and the Portal displays.
I still wouldn’t buy one, but since I have one due to a gift from a well intentioned relative… it might now get some use in my house 
I guess I’m just in really snarky mood this morning so take this and my other tome today with a grain of salt…
PS: just to be at least slightly fair, the physical hardware in the portal devices is actually decent, but again you know, Facebook…
No Alexa, Google Home, Apple Home or Facebook portal in my home. Because, you know, data pirates.
Just as a follow up on this, sort of, but several retailers are quietly clearing inventory of the devices.
I haven’t seen actual ads for them, but one of my engineers was in Bed Bath And Beyond and purchased the Portal Go which originally was selling for $199 on clearance for $69. He’s going to use it as a portable second display with duet and it also can double as Bluetooth speaker, so at $69 that seems a decent buy.
I must admit I never looked past the Meta/FB label, but at that price maybe I need to figure out if it will work without logging into FB.
I might get behind a FaceTime version of the device to keep up with my aging parents.
That’s a good question actually. I will likely at some point try it and if I do, I’ll let you know. As I said in my original post, we were gifted one (not the portable one alas) but it’s just been sitting in the box since we got it for similar reasons you mention, though I was planning to try it with Duet at some point, out of curiosity if nothing else