< i > ( insert mode )
Leave the first few lines as they are.
PS1="[\u:\w]$ " ( a space between the $ and " ) ( this will set the prompt like mine above )
< Esc >
< ZZ >
Close the console, open it again and you'll see the prompt has changed !
Some examples:
PS1="[\H:\w]$ " will give the old
[localhost.localdomain:~]$
PS1="[\u:\d \t @\w]$ " will give
[bruno: Tue Apr 29 19:04:59 @~]$
PS1="[\t \u@\w]$ " will give
[19:04:59 bruno@~]$
If all this was way to easy for you and you want something really different, with colors and shapes, have a look Here
More basic info Here
Your 'root' prompt will not be changed, this makes it even more easy to notice the difference between being root and current user !

Bruno
-- Apr 29 2003 ( Revised Dec 13 2005 ) --