The VCG tool reads a textual and readable specification of a 
graph and visualizes  the graph.   If  not  all positions of 
nodes are fixed,  the tool  layouts the graph using  several 
heuristics as reducing  the number of crossings,  minimizing 
the  size of  edges,  centering of nodes.  The specification 
language of  the  VCG  tool is nearly compatible to GRL, the 
language of the edge tool, but contains many extensions. The 
VCG tool  allows folding of dynamically or statically speci-
fied  regions  of the  graph.  It uses  colors and  runs  on 
X11. (An older version runs on Sunview).

WWW: http://rw4.cs.uni-sb.de/users/sander/html/gsvcg1.html