I'm going to be writing a Windows application using the .NET framework and C#. The application will need to store relational data which will be queried, joined and processed.
Previously I've done this using SQL Server, but that is a total overkill for the application I am now making.
What's the simplest, easiest way to store relational data in my application? If I was on a Mac, I'd be using SQLite. What's the .NET equivalent?