I can count!

Well, with the help of #xabacus, an #x11 "game" which simulates how an #abacus works, and also how powerful computers have become!

https://www.ibiblio.org/pub/X11/contrib/applications/xabacus.README

This version I'm running is 5.5.2 released in late 1999. It still compiles to this day without any modification from myself.

In fact, out of the same code base, I have two versions. One using the X Intrinsic Toolkit, and the other using #motif.