Thinking about future technologies, and how they could be made real today, i find it's important to follow a "way-out" process and then scale it back to the realm of the near-term possible and the presently possible.
For example: a device which would interface with all others one has and which could be used as an input/output, or remote control/monitor, for each device.
Way-out solution: a microchip in my skull. ;) Directly recieves input and transmits thought-based outputs etc. Useful for computer interface, TV/PVR remote control... grocery list maintenance (hehehe had to throw that in).
Near-term solution: tablet type "computer" device. Bluetooth as the transport between it and computers, TVs, PVRs, game consoles, cellphones, etc. Heck why not the cellphone? Once it does voice recognition and the interfaces to all the external devices are standardised, etc. technically possible. Politically tricky because cellphones aren't open-source, or easily hackable for that matter.
Present solution (assuming all your devices have the necessary transport support, i.e. Bluetooth.): Apple iBook (with touchscreen and Inkwell handwriting recognition) is a perfect candidate to develop the beginings of such a networked environment.
It is possble right now for me to sit in my living room, type a letter and have it automatically archived on my main computer, upstreamed to a blog and emailed to a friend. However, and again this depends on the other devices having the capability, so it is also a political thing, the iBook could also be aware of the TV. I could turn it on and change channels and otherwise control it. meanwhile the PVR is broadcasting it's existence and it's set of control possiblities. Accessing it I get on my iBook the control console check local listings and set it up to record or download a movie later. Incomign phone call automatically announces it self and allows me to see who is calling. With GPRS data optionally I avaliable I could tell where the callis coming from too.
Let's look at what is required and what exists to fulfill those requirements:
Hardware layer: Bluetooth for I/O, 802.11x for data transfer. (Built into iBook.)
Transport layer: TCP/IP (ubiquitous)
Application layer: HTTP, zeroconf, SOAP et al.
Data layer: XML, RDF, SVG. MPEG-4. AAC. videogame data formats...
I realise it is very possible that Sony, or Apple for that matter, are already playing with this stuff.
Wish I was in on it. Hmmm.