http://www.suasnews.com/2012/07/17494/laser-powers-lockheed-martins-stalker-uas-for-48-hours/

This is real Hi Tech stuff, almost in the realm of SF.

Practical (commercial) realisation would, of course , be a long way off though. Still very exciting!

check this link below

http://lasermotive.com/wp-content/uploads/2010/04/Wireless-Power-for-UAVs-March2010.pdf