Well, there was the Commodore SX 64. Not exactly lap sized but portable for sure.
https://de.wikipedia.org/wiki/Commodore_SX-64
It weighed 23 pounds. It was approximately as portable as a tower PC. You could schlep one around, but it'd get heavy after a while.
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It weighed 23 pounds. It was approximately as portable as a tower PC. You could schlep one around, but it'd get heavy after a while.