1)   Schematic 3.17
Schematic is a diagramming tool that allows complex diagrams to be drawn with ease. Schematic allows you to combine text, pictures, shapes and connectors to create clear and informative diagrams. UML, Electrical, Network, DFD, ERD plus many more...
graphics, UML, Electrical, network, flowchart, diagramming, tool, windows, DFD, ERD,

 2)   GoDiagram 2.5
Build custom interactive diagrams, network, workflow editors, flowcharts, or software design tools. Includes many predefined kinds of nodes and links. Flexible, powerful, extensible. Many useful samples. Optional automatic layout & instruments.
.NET, Windows Forms, Control, Diagram, Graph, Network, Editor, Flowchart, Workflow, Dataflow,