Efficiency in computing project/Brainstorming

Suppose we wanted to have a power device, that was efficient. Powerful, but efficient...

What would that look like? ....

GPU/multicore....

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A device... lcd/quasi epaper (glare free) on one side

solar panel on other

...

wifi...

memory...

usb... maybe..

processor...

power on off button...

speaker...

camera...

weather resistant..

microphone...

linux...

blue tooth..

accelerometers..

gps

hmmm... ... ... .. . .

.

wimax? cdma?

light - thin - maybe ~8 x ~6 x =<.25

durable>