Stuff

!!                  Last command (sudo !!)

!*                 Last command's parameters (vim !*)
!^                 Last command's first parameter
!$                 Last command's last parameter

!?ls<tab>          Command and params of last `ls` command (sudo !?mv<tab>)
!?ls?:*<tab>       Params of last `ls` command

*(m0)              Last modified today
*(m-4)             Last modified <4 days ago

Change default shell

chsh -s `which zsh`