How to make a foxhole radio (no batteries required!)

This is soo cool – this is a way to make a radio, similar to what the GI’s in WWII did. It requires no batteries, and you just need some wire, a razorblade, some pencil lead and a few safety pins.

What amazes me the most is this : IT DOES NOT NEED BATTERIES ! It’s exclusively powered by the radio waves.

Here are some other links :
Bizarre labs : The history of foxhole radios
Bizarre labs : how to build them (with schematics)