I'm using a pg json column to store data as a second source of truth for data that is primarily held on a separate microservice.

The schema on that end is pretty intricate but to prevent hitting two services for certain types of data, we just dump it to a json column.

Furthermore, for a personal project of mine to help me with productiving / daily schedules, i'm using a json column for a to-do list in the schema of

{[some_todo_item]: boolean,}

which can't traditionally be represented in pg columns as the to do items are variable.