Well, not so random graph generators, for there is an algorithm to choose and parameters to input. I call it random because it's meaningless:
CALL apoc.generate.ba(1000, 2, 'Person', 'FRIEND_OF')
This example uses the Barabasi-Albert (ba) model to generate a thousand nodes with the label Person that have two FRIEND_OF relations. As Person is a common label, each node will have a name property, which looks as follows, added automatically:
Be aware that this can create the relation from a node to itself, which is rather funny with example. So to find all the People who are friends of themselves, ...