jnet
Network and graph visualization tool
plus
Pick color for currently selected nodes:
(To select nodes use:
Click on node for single node selection;
Alt+click on node for selection with neighbours;
Alt+Left and move mouse for selection by rectangle;
Click on empty space for cancel selection.)

Size of nodes:
 
Size of edges:
 
Background color:
Boundbox:
Force-directed layout:
View in two dimensions:    with 2D style:   
Stretch mode:
Labels:
Position labels:    
Command line:(example: "set echo top left; echo JnetPlus")