If you have secrets you prefer remain that way, or just feel like reliving the rush of Cold War espionage (nuclear fallout notwithstanding), then the Spy Coin Edition ITS Challenge Coin ($30) is for you. For this variant, ITS and Spy Coins began with a nickel plated solid brass coin, then hollowed it out to conceal a micro SD card as opposed to the microfilm Cold War operatives were known to sock away. A short primer for the uninitiated: challenge coins have been around since WWII where they were made tradition — serving as symbol for soldiers to prove their membership in units. Today, there’s a thriving community centered around collecting these coins.

Author’s Note: Need more ideas on what to store on your hidden microSD card? Give this a read.

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