We've already acknowledged the historical significance to mobile computing of Psion's Series 3 and 3a handhelds , but while those models made fortunes for Psion and turned the company into a household name, there would've been no 3a without the Organiser range. And without the Organiser, there would've been no Organiser II.

Fancy a small, lightweight laptop computer with a great keyboard, built-in printer, infinite storage and a battery life of up to 40 hours? Then whizz back 26 years and bag yourself an Epson HX-20. This little retro-beauty still looks pretty nifty in the modern age — so imagine just how extraordinary the HX-20 must have seemed when it was launched in 1981?

“You’re acquired!”. We can’t help wondering if that’s the little joke Rupert Murdoch muttered to himself, shortly after wresting Amstrad from Alan Sugar. Of course, the sale of Amstrad comes as no surprise — these days the firm makes little else other than digital TV set-top boxes, and Sky is pretty much its only customer. Looked at another way, thanks to The Apprentice, Alan Sugar is a bigger star now than his company could ever again hope to be. However, things weren’t always so marginal for Amstrad.

In an age where sales of laptops are soon to outstrip those of desktop PCs, it’s hard to conceive now quite how revolutionary the IBM ThinkPad must’ve seemed just 15 years ago. Back then, a portable PC meant almost anything but portable. And then along came IBM.

Surely everyone remembers the Palm Pilot? It was the PDA du jour for the second half of the 1990s and anyone who was anyone owned one. If you had a busy life, the details would be stored electronically on your Palm Pilot. Except... the first model wasn't actually called that. No, the very first 'Palm Pilot' was made by US Robotics in 1996, and it was called the Pilot 1000. 

Back in 1981, the state-of-the-art portable PC was quite literally the size of a suitcase. Yes, it had a handle, but at nearly 11kg (25lbs in old money), you needed the upper body strength of Lou Ferrigno to lug the Osborne 1 around.

Actually, since it required a mains socket for power, it was about as much use out and about to the travelling executive as a washing machine on a trolley is a roaming domestic (although it was still small enough to qualify as hand-luggage on a flight and an optional, enormous, battery pack was also available).

If ever there was a past-it portable that deserved to thrive in the modern world, the Psion Series 3a is - or was - it. And in a way, it still does. Models still regularly change hands on eBay and there are plenty of companies still offering services, software and repairs for it.