Four-Space Visualization of 4D Objects: Mathematical and computer programming oriented approach. Discusses wireframe rendering and ray-tracing.Fourth Dimension: Tetraspace: A discussion of rotation, levitation, wheels, and bodies of water. Classification of "rotatopes" (cubes, spheres, and cylinders), and a Java applet to visualize projections and intersections of the shapes. Includes book reviews, a glossary, links, and a forum.Hyper Dimensia: Tutorial which aims to give readers an understanding of the fourth dimension by having them use a java applet to rotate a cube and a hypercube to see multiple views of the shapes at once.HyperCube by Harmen: A short introduction to the fourth dimension, plus a hypercube java applet game.Hypercube's homepage: Philosophy, math, and cosmology related to the fourth dimension.Hyperspace Structures - Exploring the Fourth Dimension: Introduction to the hypercube, hyper-torus, and approximation to the hypersphere. Page includes Mpeg movie clips to illustration the various objects.Hyperspace Travel: Images and animations of a couple of four-dimensional objects, along with the math and source code used to produce them. Links to software to interactively visualize four-dimensional objects.Miscellaneous Mathematical Musings: Introduction to dimensions, multi-dimensional geometric units, and formulas for calculating higher-dimensional phenomena.Thinking 4-d: Focuses on helping the reader to conceive of the fourth spatial dimension, and in particular discusses hypercubes and hyperspheres.