What is your single most favorite command-line trick using Bash? [closed]

Answer 1

I have got a secret weapon : shell-fu.

There are thousand of smart tips, cool tricks and efficient recipes that most of the time fit on a single line.

One that I love (but I cheat a bit since I use the fact that Python is installed on most Unix system now) :

alias webshare='python -m SimpleHTTPServer'

Now everytime you type "webshare", the current directory will be available through the port 8000. Really nice when you want to share files with friends on a local network without usb key or remote dir. Streaming video and music will work too.

And of course the classic fork bomb that is completely useless but still a lot of fun :

$ :(){ :|:& };:

Don't try that in a production server...