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Solar Death Ray

Dreaming of world domination? Get started by building your own Solar Death Ray

The Solar Death Ray works by reflecting the light of the sun from 112
mirrors onto a single spot. Anything in the spot (the target) starts to get
hot.
…
Using some basic principles of Black Body Radiation, I estimate that the
Solar Death Ray can heat things up to between 500-600 degrees Celsius
(930-1100 degrees Fahrenheit) under good conditions

Several targets like a America Online CD, one rubber ducks and a mobile phone have already been eliminated and more target suggestions are requested

Via [Hack a day]