What if I knew I'd have 30 hours no adapter to charge device.
Would I then not allow certain features, or in general want the device to be a bastard for power, like not allowing LCD to be too bright? Or put LCD off quicker?

What if GPS or network provider is non-flatfree, roaming instead?
Would I then want to disable certain auto fetch stuff? Or enable caching proxy which compresses pictures instead? Lower SIP quality? These are examples for the point here is to have a 'mode' defined by the user which gives 'acceptable quality' but 'takes into account non-flatfree'.

And some things... I have no idea, how much data for example MySpace or Facebook IM extensions use because I don't know how they exactly work. If they don't use an API but use HTTP + HTML and then parse the JS then they're quite 'bloated' so to say.

So, I think, for research purposes, some kind of traffic accounting on user processes is very interesting (much like powertop, htop, iotop for other statistics)