add shell arguments

slides/shells/shells.md

@@ -48,6 +48,7 @@ Protip: for a faster machine, make `sh` a link to `/bin/dash`.
 ## zsh
 
 - `for x in 1..10`
+- great autocompletion
 
 # Bash Advantages
 
@@ -94,6 +95,8 @@ function wotsa(){
 - `type $whatever`
 - `.inputrc`
 - `PS1=foo`
+- `^$` for first argument used
+- `!$` for last argument used
 
 # Fun with Bash