
WebUrbanist has an interesting gallery of time capsules old and new. The prize for most ambitious "expiration date" goes to the Svalbard Global Seed Vault in Norway--WU claims barley seed samples interred there may remain viable for as long as 20,000 years. For time capsule enthusiasts, the germane Wikimedia Commons Category also makes for interesting browsing. [Thanks, Billy Baque!]
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