I'd put in samples of all the stuff we're digitizing, like examples of photographic film negatives, newspapers, magazines, and books... stuff like that could be a real novelty to people in the future.

Also, if the electricity grid ever fails, it would be possible for vast amounts of history, culture, and civilization that we're digitizing to be wiped out and forgotten the way the books of the Nag Hammadi library had been thought lost, but then got rediscovered in the middle of the 20th century (not to be confused with the Dead Sea Scrolls).

We knew that such a thing as the Nag Hammadi texts existed from references made to it by other writings that did survive, but we didn't know what the Nag Hammadi texts were nor what those texts actually said, so it was a mystery until they were found in the 4rth centuries version of a time capsule, and their rediscovery totally changed everything we know about the evolution of early Christianity.

The Nag Hammadi texts were mostly Gnostic versions of Christianity, and in the 4rth Century after the Council of Nicaea the followers of the Paulian-Trinitarian interpretation of the life of Christ went on a book-burning binge, intent on wiping out all memory of the Gnostic interpretation of the message of Christ, and which was the dominant form of Christianity in the north-eastern parts of the Roman Empire.

Some Gnostic-Christian monks saw the book-burners coming, and so they hid the Nag Hammadi texts in a "time capsule", to protect them from the book-burnings, with the hope that someday they would be re-discovered by a more enlightened people who wouldn't burn them, and that's what happened...

... And now we have a fantastic understanding of what was really going on back then that had been totally lost to history, with everyone believing that the Paulian-Trinitarian version of Christianity was the only one to have ever existed (It was Simon, Philip, and to some extent Thomas who taught sayings of Jesus with an interpretation that to Gnostic-Christianity, and the Paulian-Trinitarian collection of books we call the Old Testament don't mention anything about what Simon, Philip and Thomas were teaching, even though they were so active that Christianity got to India and China from them).

... Which means... Time Capsules *are* a good idea!

We could loose a *lot* of civilization by digitizing everything followed with a power-grid failure, so we should be microfiching all our books and sticking that in a time capsule too.

I'd also have the physical photographs be lots of pictures of what things looked like in the region before the climate changed.