‘Going through a second childhood’ has acquired new overtones with the advent of nanostalgia — a sentimental (and fashionable) desire to celebrate or relive the very recent past.

Nanostalgia. The tendency to feel nostalgic over events, such as movies, that concluded only seconds ago. Krug champagne, for example, celebrates in its advertisements its capacity to deliver nanostalgic moments.

If you are thinking about how much you enjoyed reading about the upcoming Lancaster County Historical Society photo exhibit in this column, you are engaging in nanostalgia, as defined by Jim Taylor and Watts Wacker in their new book, "The 500-Year Delta: What Happens After What Comes Next."