note - all of these programs are for IBM PC compatibles, I did not create Macintosh versions - sorry
Executable programs - requires PKZIP or equivalent to extract
Fractal program - older program (1980s) that I wrote in Turbo Pascal - will create Mandelbrot and Julia sets, as well as show the trajectory of a point or a set of points in the Mandelbrot or Julia sets - this latter feature is not available in other programs I have seen and it is interesting if you are trying to understand strange attractors. It also generates several other types of graphics. Shareware Party - this program creates a dynamical system that you can think of as a simulation of the behavior of persons at a party - it uses F=MA and doubly integrates acceleration to update position of each object as it moves around the screen. Same sex repels, opposite sex attracts, etc. Primitive graphics but interesting behavior. Tubo Pascal, Freeware (it says to send $10 for a current version, but I am no longer updating this program, so it's free, although I will be happy to accept $$) 
Source Code
Note- as author of the following programs (except where noted in the
source code), I retain copyright to all of this code. You may use it for
educational purposes. If you wish to use any of this for other than
totally non-commercial educational purposes, you may purchase the rights to use
the source from me for a modest fee. Note that these files also require
PKZIP or equivalent. Contact me at 
Bounce.pas - source code in turbo Pascal for a program that draws waving lines and various other shapes - a DOS screen blanker, not a TSR (terminate and stay resident) program Party.pas - source code for the party program, above Fractal generator source code - about 10,000 lines of Pascal, most of it creating menus and things, to make the fractal program above. Note that because this was so long ago, I am not certain taht this source is exactly the match for the above program, but it is the best I have. Window20.pas - source for a window type interface for turbo Pascal - not to be confused with a product from Microsoft. This was available for DL quite some time ago, I do not recall the source. I am not the author of this program.
Special software that I didn't write but that I really love
Fortuna.exe - Fortune cookie program - a wonderful piece of Windows software written by Alex Van Boxe in the mid 90s and distributed as freeware - this will display a pithy saying when you execute it - I put a shortcut to the executable in my startup folder. My contribution is to add additional sayings to it's database of clever and insightful thoughts. There is a web site (www.fortuna.com) that promises a new version sometime. Download this and run it - we all need some light in our lives.
last updated 07/14/2021
