The goal of the project Graph Morphism Juggler is to develop a full-featured tool to assist research in algebraic graph theory.
The current version already features an intuitive graphical user interface and rudimentary methods to calculate graph endomorphisms, factor graphs and products of graphs as well as a TeX export function.
Plans for future versions include features like enhanced endomorphism sorting, representation/categorization, green's relations, epi/mono factorization functions with calculations of epimorphism distortion spectra, graph congruence (semi-)lattices, visualized N- and polyhedral Hom-complexes as well as analysis tools for topological properties.
You find our project page here: http://sourceforge.net/projects/graphjuggler/