Enrico pointed me to this curious empirical study of the effectiveness of aluminium foil helmets conducted by MIT people (Ali Rahimi, Ben Recht, Jason Taylor, Noah Vawter). Their point was to examine the efficacy of different aluminum helmets often employed by paranoids who want to protect themselves against invasive radio signals. They actually examined 3 configuration using a $250,000 network analyser.

Here are the results:

"we find that although on average all helmets attenuate invasive radio frequencies in either directions (either emanating from an outside source, or emanating from the cranium of the subject), certain frequencies are in fact greatly amplified. These amplified frequencies coincide with radio bands reserved for government use according to the Federal Communication Commission (FCC). Statistical evidence suggests the use of helmets may in fact enhance the government's invasive abilities. We speculate that the government may in fact have started the helmet craze for this reason. (...) The helmets amplify frequency bands that coincide with those allocated to the US government between 1.2 Ghz and 1.4 Ghz. According to the FCC, These bands are supposedly reserved for ''radio location'' (ie, GPS), and other communications with satellites. The 2.6 Ghz band coincides with mobile phone technology. Though not affiliated by government, these bands are at the hands of multinational corporations. It requires no stretch of the imagination to conclude that the current helmet craze is likely to have been propagated by the Government, possibly with the involvement of the FCC. We hope this report will encourage the paranoid community to develop improved helmet designs to avoid falling prey to these shortcomings."

Why do I blog this? found the project weird enough to be spotted, especially as it shows the irrationality of the aluminum craze.