I remember during one of my many visits to the Smithsonian museum in DC (mid-80's). I was wandering around in the computer section and spied an unidentified device.
It was an approximately 4"X6"X2" block of aluminum with an odd looking PCB mounted on its top.
I asked a docent what it was. He responded that it was an experimental, 2k memory "brick" from IBM.
It had two small port tubes in the Al block and I asked if he knew their purpose. He said they were for the liquid nitrogen used to cool the "brick"...
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