In this episode of Computer Chronicles, we get a look at portable computers from 1987. Our definition of portability has changed over the years, from 1975's IBM 5100 (what we used to call a "luggable" computer) all the way to today's ultrabooks, which are finally actually "notebook" sized -- and still have halfway decent battery life.

In 1987, having a portable computer of any kind was kind of amazing. "It's no more cumbersome than a case full of binders," says an announcer describing an HP portable carried by a businessman -- who also carried an outboard disk drive and printer (!) for "the inevitable hard copy" of reports. This cutting-edge device had a tiny monochrome LCD screen, a full-sized keyboard, and had its software burned into ROM. Wow. (It also had a modem to dial up the home office, which was genuinely impressive albeit clunky in the extreme.)

I know many of you are reading this article on laptops (I'm writing it on one), or phones, or tablets. Want to see what portable computing tech was like just 26 years ago? Tune in and freak out (and keep your eyes out for the "cellular telephone" at 5:30, with a battery pack the size of a car battery).

At 16:00 note how we did GPS in 1987. It involved a tripod-mounted receiver, a portable computer, and a lot of calculation. The units cost $40,000 each. At 19:45 we see the Dynamac, the first portable Mac, weighing in at 18 pounds (Apple would release their own two years later at "just" 16 pounds -- powered by a lead-acid battery).

What was your first portable computer? Mine was an IBM ThinkPad 701, best known for its "butterfly" keyboard that slid out when you opened the lid, giving you a full-sized keyboard on a subnotebook sized computer. It was a pretty slow machine, but it was super small and portable for its time!