Cosine Kitty stayed up all night thinking about math...

Computer graphics

• Read my book Fundamentals of Ray Tracing

Chess programs

• Chenard - my freeware chess program (with C++ source code) for Windows and Linux.
• Flywheel chess engine for browser-based chess.

Time

• My home-made digital clock!
• NistClock - C# .NET program for reading from NIST atomic clocks on the Internet.

Astronomy

• Astronomy Sky View - Enter your longitude and latitude, and this will show you what celestial objects are in your sky.
• Solar System Calculator - Javascript engine for astronomy calculations.
• Astronomy Calendar - Browse a dynamic calendar that displays astronomical events.
• Astronomy photographs that I have taken.
• Angle Calculator - Given three stars and angle measurements, calculate where a planet is.

Math and Physics

• Electrons on a Sphere — a simulation in your browser.
• Measuring gravitational acceleration with a pendulum
• Dropping a pebble from outer space
• Unit Conversion Tool - Javascript web tool for doing sophisticated unit conversions.
• Azimuth/Distance calculator - Given latitude and longitude of two points, calculates compass direction and distance of one as seen from the other.
• Latitude/Longitude calculator - Given starting latitude, starting longitude, compass direction, and distance, calculates the resulting latitude and longitude.
• Polynomial Equation Solver - Finds complex-valued solutions for cubic, quadratic, or linear equations.
• Make your browser calculate π to 1000 decimal places!
• Batch file for calculating π as featured on The Daily WTF.
• Make your browser calculate nth roots to 1000 decimal places!
• Rubik's Cube Nuggets
• Cubical Network of Resistors

Mandelbrot Set

• Mandelbrot Orbits - A new way to look at the Mandelbrot Set, using Newton's Method to find complex values that repeat every n iterations.
• Mandelbrot Orbital Boundaries again, this time solved algebraically.
• Mandelbrot Polynomials - A look at the algebra underlying the fractal complexity of the Mandelbrot Set.
• Mandelbrot fractal area estimates - My own computed estimates for areas of the Mandelbrot series of fractals.

Other Stuff

• Lightning detector circuit
• Radio receiver circuits
• The Qwibnar Zone - Thanks to archive.org, my old web site lives again!
• Don's Office Art
• GeekNet Inter-Office Telegraph System
• Sudoku Freeware I wrote, with source code!
• Arduino microcontroller projects
• Homemade HDTV antenna
• Recipes that I have personally kitchen-tested.

Friends who do cool things!

• Weed Killer by John Schultz. A cool utility for cleaning up old files based on user-defined patterns and schedules.

Contact me :