Databases in your writing business

How are you using a database in support of your professional writing? Here are eighteen database ideas you might create for yourself to be more efficient, organized, and productive. Confluence Book Services
Confidentially, I like the last two best:
17. Organize notes and backstory bios of your fictional characters and locations.
18. Run your brainstorms into a database: make it a place to save the half-baked story ideas, with fields that may link them together over time in ways you would not have otherwise seen.