So who cares? A lot of people leave on their home PCs all the time anyway. Well with a little magical techno-tomfoolery that PC could become a web server(think blog), email server and web-calendar, an in home music server, wireless access point, home security device(webcam), robotic pet feeding device, podcast server, firewall, and home entertainment server with DVD (plugged into a HDTV). Right now you need a fairly strong technical background to get something like this up and running (I'm going to try at my new house in about a month) but it's not impossible by any stretch.
When someone puts this all in a little box that runs quietly and costs less than a couple hundred dollars AND is really easy to setup and configure, crazy things will begin to happen. The major issue right now is that a static IP costs a bit more money than the typical broadband connections but IPV6 and DynDNS should solve that problem.
Right now a lot of companies are releasing crippled open source versions of their premium products to gain publicity but there is a huge risk that the community will fork the project and add improvements available in the commercial versions. It would be legal too. Software is becomming a commodity so businesses are selling new features and services to make a living in the Open Source software industry. I get the feeling that ubiquitous broadband, cheap storage and reliable distributed networks (bittorrent) are squashing even those niches. Maybe offsite backup for these increasingly complex home servers will be the last bastion of profitable IT in a few years. Then that'll go away when someone invents encrypted distributed file systems running in a RAID 1+ array so all of your close family and friends can participate in the offsite backup of your family photos and other data.
Then... all of us techies will be forced to come out of our caves and solve problems that really need solving like Open Source/Creative Commons licensed education for developing countries. I believe in accelerating change and I think things will be much different, mainly for the better in five years.
Some relevant links:Epiacenter