"I assume it is capable of boiling water.."

This video of one of the prototypes in action , may give a better idea of how it works :
http://www.youtube.com/watch?v=JmHCIBvI6vE

Anything that needs me putting my hand into my pocket is expensive but looking at commercially available somewhat similar stoves (without the charger bit) like the Bushbuddy or the FourDog Bushcooker , it looks pretty good to me.
If you add the weight and cost of a solar panel and bits you need to connect it to your device , then both weight and price may not be too bad.
Mostly I was thinking about areas where wood is plentiful but the sun is scarce...
Like a lot of this type of gear, it is a niche product so no good at all for most but potentially great for some.
Franco