3D Dewey Data Visualization [syedrezaali.com] is a visual exploration of "3D Space, particle systems, OpenGL and Java, alpha blending, bill boarding, user interactivity, self-organizing algorithms (Kohonen), and electromagnetic attractions & repulsion". It is also a rather, hmmm, random looking 3D data collection of one year of transaction data (e.g. books, DVDs) from the Seattle Public Library. Each particle somehow represents the category and how many items where checked out in that category.
More visual candy here.
Via Visual Complexity.