[mrmcsoftware]

I don't know if I would recommend it, but I've noticed that in the past, whenever I moved to a different type of computer/OS (Amiga, MS-DOS, Windows, etc.) or language (Java, Javascript, etc.), I ported my biorhythm program to the new system/language. It starts out simple - just strings, math, file/screen input/output, then progresses to graphical plotting of the biorhythm curves. It's a simple algorithm. Disclaimer, I don't know if I believe in biorhythms, it's just something interesting and a flashback to my childhood in the 70s.

Basically, I would say the easiest way would be to choose something you've already conquered in a language/system you already know. That way, you're only tackling one new thing.

BTW, it wasn't always biorhythms for me - I originally wrote my Mandelbrot program in Pascal, and taught myself C in order to convert it to C so it would run faster.

[Tempest1981]

Mine was sunrise/sunset and phases of the moon. And more graphical: planet orbits, watching for alignments.

[mrmcsoftware]

Coincidentally, my biorhythm program would tell you various things about yourself (birthstone, zodiac traits, yin/yang, Chinese animal, numerology, but also the phase of the moon the day you were born). Yeah, I threw in everything I could find/calculate.