Unfortunately there are not that many Psion pages left on the we-we-we :-)
But I did find some. Here they are:
A very interesting article by David Savery on battery replacements for the Psion Revo
Very fascinating page(s) on 'Getting the Psion 5mx on the internet' (!). It will not run YouTube or provide the content that we are used to today but it can provide a 1990’s internet experience!
A very interesting article by David Savery on the Psion Series 5MX disassembly and screen cable repair.
Article called 'Psion sidecar Part II', where the author dives in a bit on the Psion Sidecar that was covered the previous week and where he adds some details to explain the RS232 connections and the switches on the Sidecar.
A very interesting youtube channel: a look at all handheld computers from the past and present with a focus on portability and usability. And of course it features many Psion video's.