Name, address, GPS localisation data, habits (like apps you often use, moments you use one device or another), gender, search terms in search engines, open web pages on a web browser, connection (other person you know), the work you do and where you work.
All kinds of things, really.
The usage is mostly advertising or identity theft.
Solium Infernum : strategy game, with a lot of diplomacy mechanisms ( like you can’t attack directly an enemy but you can ask them to pay you tribute, if they refuse you can attack on response).