I used hstore in an existing database for metrics. It allowed me to add different metrics in the code, rather than having to update the database for new metric

I used hstore in an existing database for metrics. It allowed me to add different metrics in the code, rather than having to update the database for new metrics, then a metrics to hstore layer that more or less "streamed" them into the database. I find it quite awesome for that case. Sometimes there is a need to unstructured data, and if you are already using Postgres, hstore is a great alternative to adding another database backend to your stack.