Example: An application built on RecallGraph
(A time-travelling mind map tool)
If you'd like to get a more hands-on idea of what it feels like to work with a versioned graph database, here's an application that gives you a taste from the point of view of an application end user.
Hivemind is a free tool that lets you create mind maps in your browser. It supports time-travel (through the change history of the mind map), tagging specific time points (planned) and collaborative editing (planned).