StoryMill - Developers and publishers of Mac, Win, and iOS productivity, home and office and writing software such as MacGourmet, Paperless and many more. Based in MN.
Airtable - Airtable works like a spreadsheet but gives you the power of a database to organize anything. Sign up for free.
Manuskript - Open-source tool for writers.
FriendlyData - Communicate with databases like a human
Novelize - Novelize is an online novel writing app designed to keep authors on track.
SpreadsheetDB - A database that you can query with spreadsheets