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From what I can see, the IA has about 10 PB of data (Wikipedia). Backblaze says they can achieve $60/TB, or $600k for 10 PB, so maybe you could build a second one for a few million dollars (?). Are there any national archives / major libraries (e.g., Library of Congress, British Library, Library & Archives Canada, university libraries, etc) that have plans for doing archival like this? It seems like an important project within the scope of these types of institutions, though the budget may be a limiting factor (both the LoC and L&A Canada have suffered budget cuts of late; I don't know what the situation is in other countries).