My last comment on powering transport has prompted these thoughts:
Will Google Earth one day become so packed full of data that you can ‘visit’ somewhere from your own living room and get 99% of the experience – thus doing away with expensive plane trips to exotic destinations?
But will the demands on your computer system be such that in order to get that experience you will have to consume as much energy (presumably through electricity to your computer) as you would by getting on an aircraft and actually going there?