Powerbooks, Model-Ts & Longevity

I've written elsewhere in my blog that machines have life expectancies; in that essay, I was referring to my Portable. But the realization is starting to dawn on me that most of my computers will, indeed, one day die. That's how it goes; nothing lasts forever. My question, though, is this partially by design or by usage?
I don't think Apple is a company that practices planned obsolescence. It's obvious to me that the contrary seems to be true; Apple still offers some of their operating systems on their site. No doubt, they would love it if you went out and picked up a brand new G5, but there is almost a sense from them that their work matters, so they continue to offer what they can to their legacy.
Other computer companies could learn from this. Last year, I received an NEC laptop... I no longer recall the model. Suffice to say, this was a very early machine, and offered some neat features, such as a removable screen and a hard disk, plus a V30 processor and built in applications. Sadly, the only thing that worked was the floppy drive. The hard drive needed to be reinitialized. You would think that one of the largest computer manufacturers would support this. They behaved like they never even produced it. The computer, no matter how neat, was essentially useless, and had to go. Pity.
Apple does better than this. But it still doesn't stop their computers from eventually getting old. Last week, I received two Powerbooks; the much maligned 5300 and the much sought after 100. Of the two, the 100 is the one that won't run. Why? Simply put, hardware failure; a series of capacitors on the back of the LCD have gone bad. Did Sony, who did the actual contracting on the 100, know that this would happen? Probably not. To their's and Apple's credit, the Powerbook 100 is a breeze to work on. I have desktops that are harder to get in to. This machine was truly designed to be serviceable, as opposed to replaceable.
This lesson has not been passed on to later Powerbooks, however. I dread the day my 540c finally has to have its hard drive replaced. Its PRAM battery already needs to be replaced, but I'm putting that off as long as I have to.
So, obviously, computers are prone to fail, eventually. Incredibly, my oldest computer, my Tandy Model 102, has been nothing but a joy. It has been through hell, yet it still continues to operate. Why?
Simply put, it's simple. No moving parts. The only glitch is the year, which according to my Model T (what we Tandy Model 100 fans call them) is 1905. Everything else is perfect.
So why couldn't Apple design something like this? In the 1980s, they did. Eventually, some of these concepts made it into the Newton line, and it can be said that the eMate is Apple's equivalent machine. But it does not have the same following. It was never meant to be used the same way, though. The Tandy was a writer's machine, the eMate an educational tool. Two different markets, you can say.
There is still a place for a device like this. With the resurgence in Apple, it would be great to see them introduce a sub-laptop that stores its files in RAM or Compact Flash, no hard drive, no CD. Just solid state, through and through.
Is there a market for that? There are machines like this already, but Apple could certainly do it justice. It could be designed to be tough yet elegant, as Apple has done with the iPod series. And if properly implemented, they could last.
But this is just a dream. For now, I just have the hope that my working Powerbooks will hang in there. My Tandy already has, and no doubt will continue to do so. There's much to be said of simplicity. They say that if life indeed exists elsewhere in the universe, chances are more than great that the vast majority of it will be microbial. Their simplicity enables them to live in conditions where more sophisticated organisms will fail. For longevity to be successful, then, manufacturers need to concentrate less on thoroughbreds, and more on bacteria. If it works that way in biology, it will work that way in technology as well.