Cytoscape is a cross-platform, open source application for visualization and analysis of networks. It is widely used in the field of Systems Biology to visualize different types of biological networks (like protein-protein interactions). It also has a plugin mechanism for extending its core functionality. Cytoscape is written in Java, so this open the possibility of using Processing to create Cytoscape plugins. I just put together a small template for creating Processing plugins for Cytoscape using Eclipse, keep reading for more details.