TRS-80 Model 100 - impressive durability ...

[50ShadesOfDirt]

... after 40 plus years, it still turns on and runs. I know I used it a bunch in the 80's, so it has survived both the "calendar" test (living in a box for decades, lots of moving abuse), and the "planned obsolescence" test (didn't immediately die after 4 years, or whatever it was back then).

Most of my new computers reach various points of failure much more rapidly, and I don't think many of them would turn back on after 40 years, much less 5 years.

The NI-CAD battery in it still seems to be taking a charge, and I've found wall-warts to work without feeding a bunch of AA batteries into it. Found another M100 on EBAY listed for parts (wanted a spare of the LCD screen & other components), got it in, and *it still works* ... these things are tanks.

Still working with this "laptop" and discovering uses for it, beyond retro "basic" programming.

[Phil_G]

Me too, mine was bought for me by work 40 years ago, its been a temporary BBS, a comms terminal, a file-transfer device, it helped me pass my morse-code test 25 years ago, and I still use it from time to time. Its the most dependable and resilient tool I've ever owned!  I've never changed the backup battery in all that time.  The Model 100 was/is an astonishing machine!
Here's the Tandy 100 driving my homebrew SC/MP, originally built in 1980:

[SiliconWizard]

Well, build quality was impressive. But it was also due to the technology they had access to at the time. In other words, to make something functional and reasonably reliable, they had to factor in quality a lot more than what we do now. And everything was simpler too.

Also, those machines made in series commonly had mask ROM chips which can have a very long life time. Many computers of the 80s still work (power supplies being common culprits). Try that with flash memory, see what they'll contain in 40 years from now with 30 years+ of sitting unpowered...