Oh, I do remember the ViewMaster, it blew me away back in 1972
I'm not usually a binoviewer man, because the reward doesn't seem worth the effort and expense to me. That's also why I missed all the LOA 3D talk on CN – I wasn't following the binoviewer forum.
From what I read so far this 3D technology could indeed be a game changer for deep space observers. Maybe I'll try it some time, but the way the Aussie dollar is going at the moment that could take a while...