Major Nelson's Xbox 360 can blog
devices can blog...it's a readable log, really. Machines often log events that happen to them, but never really in a human readable form with style and prose. This illustrates that it's definitely amusing and possible, especially if personality engines were invented and utilized.
But in the end, the devices reflect its owner, and how they live their lives. As more and more devices log your life, you can compile stats and see how you actually live it in the long run, and be able to make changes and adjustments if you wish. This, to me, would be the ultimate personal information. Privacy in this term would have to be strictly protected.