Re:Gemini PDA: 20 years on, meet the all-new Psion Series 5
by jecel on Friday December 01, 2017 @11:23AM
(#15824822)
Even the lightest old APL computers I am familiar with, the Ampere WS-1 (Japan 1985) and the MCM 70 (Canada 1974), were giants compared to the Psion 5.
http://www.old-computers.com/museum/computer.asp?c=66 http://www.old-computers.com/museum/computer.asp?c=346
I am pretty sure you weren't thinking of the IBM 5100.