Simulations

Falling into a Black Hole
Shows what it would be like to approach, orbit, and finally fall into a black hole; created by Andrew Hamilton (University of Colorado at Boulder).
http://casa.colorado.edu/~ajsh/schw.shtml

Geometry around Black Holes
Web exhibition with visualizations of various properties of both Schwarzschild black holes and rotating (Kerr) black holes, such as curvature, light cones, and the gravitational frequency shift, produced by the Danish physics student Michael Cramer Andersen.
http://www.astro.ku.dk/RelViz/cramer/text/geom_web/node1.html

Orbits in Strongly Curved Spacetime
A JAVA applet which simulates the orbit of a low mass test particle orbiting a non-rotating black hole. Created by John Walker.
http://www.fourmilab.ch/gravitation/orbits/

Step by Step into a Black Hole
Simulated images of a gradual descent into a black hole, provided by Ute Kraus (Theoretical Astrophysics group at Tübingen University).
http://www.spacetimetravel.org/expeditionsl/expeditionsl.html

Numerical Relativity: Towards Simulations of 3D Black Hole Coalescence
Review article by Ed Seidel (then at the Max Planck Institute for Gravitational Physics) which discusses recent developments in numerical relativity. The main focus is the progress made in simulating the evolution of fully three-dimensional black holes. <small>(June 23, 1998)</small>
http://arxiv.org/abs/gr-qc/9806088