The answer is the Dunedin City Library's latest annual book sale - promoted as a "gold rush" event - which began yesterday, in the library's basement car park.
The sale continues from 11am to 4pm today and tomorrow.
"Celebrate Otago's gold heritage by heading underground and digging for literary gold," a library promotional notice advises, also reminding customers to bring their own bags.
Library collections and access manager Linda Geddes said sales had been steady since yesterday morning, and there had been waves of higher demand.
"We're happy", and bargain-hunters also seemed pleased, Ms Geddes said.
About 30,000 books were being put on sale, mostly non-fiction, as a result of trimming back some older, non-New Zealand material, she said.
Not everyone was a reader, but among those who were, some were still "completely captivated by books".
"We can't put enough in front of our customers," she said.
Much had been said about the benefits of reading books on screen, but physical books had "absolutely" kept their magic for many people, she said.
