Symbolics veteran here...

Ahh, fond memories.

Indeed, we had a Foonly. I don't know the model number, but it was a single rack unit. We used it as a server, software development, SUDS electrical CAD, etc.

And yes, it's name was "pos". That was never meant to be particularly nasty; more like an optimistic end-of-an-era kind of thing.

And I have to say, it was pretty reliable. I can't remember it ever dying.

At least two early Symbolics folks were involved with Foonly, so I assume this was a prototype unit obtained in some deal.