blocktube(6x) on Linux
The text b3cd70e17aec, as Debian 10 (Buster) shipped it.
draws a swirling, falling tunnel of reflective slabs
Flags it lists
-
-changetime -
-delay -
-fps -
-holdtime -
-no-fog -
-no-texture -
-root -
-visual -
-window -
-wireframe