Particle systems are an effective tool for visualizing information in a variety of contexts. This paper focuses on the use of surface-constrained particles to visualize information about the surface. We have designed a particle system programming framework consisting of behaviors, attributes and shaders that allows users to rapidly create, debug, and deploy particle systems for sensing and extracting specific surface information and displaying this information in an visually effective manner. We also introduce a simple particle system "little language" to facilitate the articulation of these particle programs. We demonstrate the flexibility and power of this framework for surface visualization with the applications of singularity detection and display, nonphotorealistic surface illustration, and surface mesh algorithm visualization.