Alcune delle risposte (imho) più belle:

• HangsAround: another nice option is always the old; dd if=/dev/random of=/dev/sda
• Obliterous:I sense a great disturbance in the Force, as if millions of voices suddenly cried out in terror, and were suddenly silenced deleted.
• hei_mailma: Too boring. What about aliasing all editors and “cat” to “rm -rf”?
• HangsAround: Very Nice, i like your style, maybe something less destructive but infuriating? alias all editors and cat to something like…  sudo date --set="shuf -i 1-23 -n 3 | tr '\n' ':' | sed -e 's/:$//g'“ ; cat 
  Sets the system time to random-ish times whenever they use the command