I walked into a fundraising sale in a nondescript building, looked down at the floor, and saw these bricks made of wood.
They form the floor of the Bastille Design Center, in a building that had been used in the 19th century to manufacture screws and bolts. Wooden blocks were common in factory floors and streets, and were especially effective at absorbing the noise and vibration of machine tools. Apparently, installing the wood with the beautiful end-grain swirls facing up makes for a stronger surface.
Location: 74, Blvd Richard Lenoir, XI. More pictures at the Bastille Design Center website.
Information on industrial use of wooden brick floors: Michigan State Physics & Astronomy Shop Floor.