I remember coming across these a looooong time ago.
i thought they were gold back then and i've found that they havn't lost their alure too much over the years
http://youtu.be/ppwohD1cvno
http://youtu.be/MFZafk0zUEE
http://youtu.be/AX928d7UIzA
http://youtu.be/xANzHUNKH8U