I'm not sure I understand the point of OpenOffice type apps on the big
screen. Why do I want to look at a screen that is much farther away
from me to see the data (which BTW you will need to blow up the font
size to see it) when I can see the same data on a smaller screen that
is physically closer to me? That said, if you really wanted to do this
it could be accomplished via an app (eg. launch the synergy app on the
TV and you can now connect your netbook to it). I think this makes
more sense (in an app) than built in functionality.
As for the logging in portion, I still want to see the average TV's
day for a family of 4. I think Alan Bell's idea is probably the best
(the separate usb keys), although I think there are some security
risks with that scenario. If someone takes my key (or just copies it)
can they now read and write all my data? Maybe we could make it read
only.
To the point of "Family of products working together". Please don't
make added functionality come from owning other Ubuntu branded
devices. Make an Android app, IOS app, Windows app, OSX app, etc. If I
wanted to have vendor lock in I would own Apple devices.