I'm looking for a library that draws lines and arrows between boxes, but the boxes can generally be plain old div's or iframe's. HTML can do the box content, it

I'm looking for a library that draws lines and arrows between boxes, but the boxes can generally be plain old div's or iframe's. HTML can do the box content, it's just the lines & arrows that are the hard part. The box connection can be the 8 compass references: N,E,S,W,NE,SE,SW,NW