Advancing in the Bash Shell
I don't use !!, or !$, because I prefer to see what command is being executed before I press enter.  For the same reason, I will never use !word.  But that's not a problem, because as others have noted bash makes it easy to not have to fall back to these.Alt-. will generally add the prior last argument into the current command, and repeated presses will cycle through previous commands.Ctrl-r will dynamically update to show you the prior command matched as you start typing afterwards, so you can confirm it's correct.Both are essential if you want to reuse prior commands but either can't trust that you were the last person using the shell, or don't want a typo to ruin your day, and possibly many other people's day as well.  That is, if you're a sysadmin using the automatic variants, I don't want you anywhere near systems I rely on, I want you far away.  Perhaps working for a competitor.