I like DuckDB but I'm not sure what it wants to be. There's always new ways to use it and it's not easy to see what's the right one.
Our data pipeline produces .duckdb files that our app downloads (it watches the asset in S3 and pulls when etag changes). Makes it easy to get BQ/Clickhouse like performance without running or paying for that infrastructure. Not perfect for all cases, but it handles a lot more than you would expect.
+1
I can't think of many use cases for this and Arrow Flight, other than moving data around.