If you're wondering where the next economic boom will come from, I think it will involve a central computer for your home that handles all of your entertainment, home controller, and computing needs.
Before you rush to tell me "That already exists," and then provide links to things that only do a few functions, let me assure you that it doesn't exist. But there is no reason to think it won't be developed in the future.
I came to this conclusion while searching for a home system that would deliver recorded TV shows and music (iTunes) to several rooms in the house, with each room controlling its own content. I was surprised to learn that no such thing exists.
It would be nice if this hypothetical system also controlled my lights and video games and security and heat and AC. I'd love it if all of my entertainment content could be downloaded from the Internet. And it should be networked with my home computers and automatically back itself up over the network. That would be spiffy.
The closest thing on the market is a so-called home media center that will distribute movies, music, and your own content to multiple rooms. It's not yet integrated with a whole home DVR to handle all of your normal television viewing. It doesn't handle lights, video games, security, heat, AC, or home computing. And it doesn't back itself up over the Internet. Plus it is crazy expensive. So there's a long way to go.
As an aside, the system would only need to back up a database of what movies, music, and video games you own, and not the actual content. If you ever needed to do a recovery, your record of ownership would allow you to download the content again for free.
I can imagine a system that backed up your top secret proprietary data to media in your home, so you can physically control it, while all of your non-proprietary stuff is backed up to a central depository that is also very secure.
I assume Steve Jobs will be the one to create this system if he has another act left in him. If he does it right, the only other computers you would need for your home would be laptops. The rest of your home computing would be handled by your home server. All you would need in each room of the house would be a monitor - that's the TV in most rooms - and a keyboard or mouse. Or perhaps by then your phone will act as a universal remote.
Obviously all the technology to make this happen already exists. It's a matter of getting the cost down, negotiating all of the various licenses, and building an interface that is easy to use. It's probably ten years out, but it seems inevitable.
[Update: I will acknowledge "it already exists" if you can point me to any link for a system that can do these two things:
1. Stream 3 different HD shows from a central DVR to different rooms at the same time.
2. Stream iTunes-selected songs to multiple rooms, each its own song, at the same time.]