<b_jonas> slashlearn euclid//Euclid is a short geeky game in which the goal is to do Euclidean compass and straightedge constructions in as few steps as possible. It runs in the browser, found at "http://www.euclidthegame.com/". It was popular among #esoteric regulars in 2016-07.

#!/usr/bin/perl
$c=unpack"C",$ARGV[0];print+($c&1?"H":"h"),"ello",($c&2?"":","),($c&4?" W":" w"),"orld",($c&16?$c&8?",":"!":$c&8?".":""),($c&32?"":"\n");