Now that Amazon has launched their cloud storage solution for users, I think there will be a return to the classic home file server to access all your stuff on the go, but the term for it will be a much fancier one--your Personal Cloud. The word "cloud" might be overkill for something you run at home, but getting at your stuff wherever, whenever certainly provides cloud-like benefits.
If you are a DropBox user you already have some of this behavior. In fact I've been tempted to upgrade the storage space, but I would never pay to store all my music on it. Now, I've had various home files servers, Personal Video Recorder servers, etc. but the idea of a server that goes beyond just "serving files" and starts to make all your important files and media available on your laptop, desktop, mobile and even iPad has so considerable merit.
After looking at a few options I settled on adding Tonido to my home Linux server. Tonido is a really impressive option that runs a server on your Windows or Mac Desktop (in the background), on a dedicated computer or on a cute little $99 computer that looks more like a power adapter than a PC.
No matter what you choose, adding a terabyte to your personal cloud as a simple USB drive. At the time I wrote this, you could get a 1.5TB USB drive for $70 on Amazon. If you would have told me even 18 months ago, I could have a 1.5TB networked drive accessible from my cell phone for $170, I would have more than chuckled.
Now this is pretty volatile storage. Only accessible when your home has internet and power, so I would put it in the 98% uptime arena depending on your ISP and other factors. Add a second drive (for real-time backup) and run your server on a netbook (so you get a built-in battery backup) and your uptime could approach 99% and we're still under $400 total. The dual-drive netbook option is what I'm configuring as I write this.
The desktop software is free, but certain add-ins could have costs associated as they are trying to build an App store like everyone else on the planet. The photo, music and file plugins are free as well as the iPhone, iPad and Android apps, so it's hard to go wrong simply trying it out.