Thinking about what makes computing a challenge. The biggest thing is that at some point we all customize and personalize our main pc, it has the layout and look and programs that we like and prefer.
I think at some point our pc will evolve as they are already evolving already, oqo, viao and the like getting smaller and smaller.
I think the PC as we know it will evolve to a small box, a motherbox if you will, that will be persistent storage device with multi-gigabytes of storage (holographic maybe?), high speed universal wireless I/O to attach to internet, keyboard, mouse, monitor.
Imagine walking up to a desk with a keyboard mouse and monitor, the motherbox in your pocket talks to the peripherals, quick biometric log on and you are active with all your stuff, your personal pc experience.
Several hours later at home the experience is repeated.
Riding the train to work the next day collapsible keyboard and mini-screen give ultimate portability.
Things to make the work are induction pad charging. This is existing technology and just needs a great way to implement, imagine your entire desktop as a surface where any electronics placed on it are charged....perfect for keyboards and mouse, as well as the motherbox.
Almost all of this is available now except for small holographic storage, which already exists and I am sure will soon be reduced in size and increased in storage.
Now the sweet stuff. Imagine a personal picture journal...a lapel camera and microphone with a time/date stamp that records...everything, any dispute on something and you could bring up the date and time and review.
All your data with you at all times, and all other data relevant to you. Medical, dental records, financials everything that you could imagine information wise always at your fingertips.
I think that e-ink will evolve to color and motion in the future making displays cheap, bendable, rollable and ultra power conservative. You could have a credit card sized screen in your wallet, that could unfold to many times the size.
Plus what about real time info on multiple screens. Your watch is simply an interface to the motherbox, a virtual screen for the system. A personal window to your information. Time, date of course, appointments, alarms of course, your personal medical biometrics, heart rate, temperature of course. Just this one feature is incredibly powerful. Like the Lid devices coming out for notebooks, a low power window into the PC. But with the possibility of so much more information.
Pattern recognition software, combined with camera system and a set of glasses (contacts) with addition of heads up display technology would give you all types of enhanced reality, called augmented reality. Basic could recognize faces and link to their contact data, you know their name, etc...You look at a theater and it gives you shows and show times. It hears squeal of tires and via location system determines you are in danger and warns you by flashing, and yelling stop in your ears.
Lots of interesting possibilities. With advances in storage, expert systems, knowledge bases this is what computing is evolving too. I really believe that with the pace of technology, the demand for information management this will be the way the future is going to play out.