@neauoire Not online or practical, but maybe fun and slightly educational. I dug up code I made in 1986 using MacForth's cooperative multi-tasking to run 4 graphical sorts at once. Syntax core was:
: MY.TASK ( --)
...
ACTIVATE<
...
PAUSE
...
STOP> ;
Required a little extra cooperation to make sure the timing was fair for the visual comparison (not just based on number of PAUSE calls).