Frozen in time

It might be a thing of the past now that digital cameras and smartphones are ubiquitous, but there was a time when you would occasionally accidentally forget about a roll of film or leave a disposable camera gathering dust, only to rediscover it some months or years later, get the photos developed and feel like you were somehow travelling back in time. It's unlikely, though, that any of your pictures had to wait 100 years to be developed, during which time the negatives were frozen in a block of ice in Antarctica.

(Thanks to Rob for the link.)