DAG Bars: An Interface For Working With Directed Acyclic Graphs (DAGs)
If you created bunch of vertical bars, and put nodes on each bar, and then connected directed edges from the nodes only in one direction (say from left to right). And you made it interactive and editable. I think that might make a nice interface for dealing with DAGs.
Let's call this: DAG bars.
(The DAG shown in figure 1 is shown in one possible DAG bars in figure 2.)
In some ways, DAG bars are somewhat related to topological sorting. Although doesn't go as far as putting a total order on the DAG (that a topological sorting does).
You could also extend this in higher dimensions. For example, in 3D use a pipe that is marked cross-sectionally, put nodes on the cross-section marks, and only connect things going in one extrusion direction of the pipe.
I suppose you could call this 3D version a DAG pipe .
(Note that when I say "pipe", I mean it in the mathematical sense, and not necessarily something with a round cross-section. For a math pipe, it is the extrusion part that is important. The concept of extrusion gives you a hint of what could be done in even higher dimensions too.)
(I don't have the tools right now to draw the 3D version this, to show in a figure.)-- Charles Iliya Krempeaux