I've just finished gathering all the parts to put together a "grandpa box". I have to credit Scott Adams for the term:
There's an interesting change happening right now: computing power is becoming so efficient, so cheap, and so distributable that we no longer depend on Moore's Law to describe technological advancement. (For those who don't recognize the term, Moore's law describes the effect that technology at any price point doubles in power and/or halves in size or weight every 18 months. This has been consistent for about the last 50-60 years.) Basically, we've passed the point where a computer that's twice as fast doesn't do you any good.
Let me compare this to automobiles. Cars get faster every year (not twice as fast, but incrementally faster). But decades ago they passed the point where faster had any additional value outside of racing. You could buy a Lamborghini Aventador to go faster than your current car does, but you would rarely get it out of first gear and never put it in third for fear of lugging the engine too much. The power is there, but it's unused for almost any activity. You could spend one-tenth the price and get a car that still outperforms what you actually can do in traffic.
Computers are at that same point now. If you look at what people are buying now, it's about the same specs as what they were buying four or five years ago. Yeah, you can get faster hardware, you just don't need it.
Think about what your computer actually does: most of the time, it is patiently waiting for you to type the next character or move the mouse a little. Maybe it's waiting on a service across the network to respond. Rarely is it working hard to accomplish a task. Any extra computing power is just sitting idle waiting for something to do... it's wasted money.
"But wait", you say, "my computer is doing more and more than ever before for me". That's not entirely true... your computer is doing less and less than ever before. The work is being done elsewhere.
Google search doesn't tax your computer at all... it sends a request to a remote service, and a few microseconds later it gets a response. The response is simple and can be displayed on-screen by even the most primitive systems (Google search results render as quickly and look equally good on a 2005-era PC as they do on your top-of-the-line system). Your first-generation iPhone (which is less powerful than the desktop computer you had 10 years ago) can handle Google just fine.
Shazam is equally easy on your system. Shazam is a tool that listens to the sound coming in on the microphone of your smartphone and tells you what song you're hearing on the radio or the PA system. Identifying music is actually a very hard task, but your computer doesn't have to do anything... it just records the microphone for ten seconds or so, sends that recording to a remote service, and then shows you what it was able to figure out. Your phone only has to record and send an audio clip (easy) and display a small table (even easier). Again, well within the ability of even the most simple devices.
Google and Shazam both outsource the task to remote servers, and that's where the real magic happens. Google has dozens of server farms with over ten-thousand computers each, and two with over 100,000 computers in them each. When Google needs to solve a problem, they set their data center on it and stand back for a few minutes, then get a result. Those computers need to be powerful, fast, efficient, and reliable. Your pocket computer does not.
And so here's the real change that's happened. All your computer does is provides a conduit between you and the powerful services you need. And a small, cheap tablet or smartphone can do that extremely well.
So what's next? The computers you carry are simply providing an interface between you and information. Since we all have different ideas of what that interface should be like, those portable computers will start appearing in many different forms. Want a big screen and headphones? Buy a tablet. Want portability over all else? Buy a smartphone. Want the computer to be hidden? Buy an earpiece that connects to a small box (about the size of an iPod) hidden in your clothing and interface with your computer using only your voice and a computer-generated voice.
About the only thing most people won't want is a grandpa box. Even laptops will go away for many users in the near future. In fact, right now over 70% of computer owners worldwide own only a smartphone and other portable systems.
Which brings me back to where I started. I'm building a grandpa box. Why? Because I'm learning how to make clustered server farms to do high-end processing on the back-end. It's just going to sit and process data, so it won't have a monitor and keyboard... that's what my laptop is for: to provide the interface. See, even us old guys can keep up with the times.