Today I Learned
Command Line Russian Roulette
Found a very funny comic on commicstrip.
nixcraft has this article that explains these commands.
[ $[ $RANDOM % 6 ] == 0 ] && rm -rf / || echo *Click*
or
[ $[ $RANDOM % 6 ] == 0 ] && rm -rf --no-preserve-root / || echo *Click*
or a safer version
[ $[ $RANDOM % 6 ] == 0 ] && echo '*Oh nooo*' || echo '*Click*'
On reddit someone saw an ad from infinum about this.