NE SUTOR ULTRA CREPIDAM
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Columns filled with numbers turned into images
ECMAScript (Javascript) library, distributed under the GPL license, that creates charts from (x)HTML tables.
Sunrise/sunset hours, all year long
GPL-distributed Python software that draws sunrise, sunset and daylight graphs.
How to make both brain hemispheres work with 52 cards
Rules and interpretation of a card game in which rules are created by its players.