Here's an interesting article about Space-Based Lasers and directed energy weapons.
The most novel idea I found in this article is :
'By tuning the resonance of a laser onto Earth’s ionosphere, you can create audible frequencies. Like some boom box in the sky, the laser-produced voice could bellow from above down to the target below: "Put down your weapons." '
I'd like to use it to tell Usama Bin Laden to: "Eat Pork, it's the other white meat."