This started from a list of tasks you give a sysadmin in a job interview, but a lot of people found it fun.
I have tried to keep it to things I've encountered in my job(s), or things close to those.
Every directory has at least four files:
task
is a description of the task (what the interviewee sees)solutiona
is how this can be solvedrationale
is why this task is therebuild.sh
builds the task itself.