A tin foil hat would be far less effective than putting a cast iron skillet on your head.
At least if it the skillet had high sides.
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@inmysocks MIT did a study on tinfoil hats (well, a bunch of bored MIT students did the study)
Turns out tinfoil hats actually amplify radio frequencies assigned to satellite communication and the US government
@inmysocks Here's the link to it https://web.archive.org/web/20100708230258/http://people.csail.mit.edu/rahimi/helmet/