title: Good graph database for finding intersections (Neo4j? Pegasus? Allegro?...)
body: <p>I'm looking for a good graph database for finding set intersections -- taking any two nodes and looking at whether their edge endpoints "overlap." Social network analogy would be two look at two people and see whether they are are connected to the same people.</p>
  
  <p>I've tried to get FlockDB (from the folks at Twitter) working, because intersection functions are built in, but found there wasn't much in terms of user community/support. So any recommendations of other graph databases, especially where the kind of intersection functionality I'm looking for already exists...?</p>