##File size
Display the biggest top-20 directories
du -ah . | sort -rh | head -20
Display largest files
find [directory i.e. ~/] -type f -printf "%s - %p\n" | sort -n | tail -n 100
##General
Acess the ascii table quickly
man ascii
Find out what process are running
top
Create and password protect a zip file
zip -er [archive] [folder]
##History
Find all SSH commands in your history
history | grep ssh
Find last 10 history commands
history 10
Find the last SSH command and run it
!ssh will surch your history for the last SSH command (or whatever command you want i.e. !ls or !mkdir) and run it
!ssh
Find last SSH command and DON'T run it
!ssh:p will surch your history for the last SSH command (or whatever command you want i.e. !ls:p or !mkdir:p) and run it
!ssh:p