OS X
How to open the iOS Simulator via the terminal
The simulator can be super useful, but equally super hard to find. Here is the path and how to open it.
Hide the desktop icons on Mac OS X
A two step way using the defaults command to hide the icons from the desktop in Mac OS X.
Display disk usage with the du command
How to display the total of the current directory or a particular directory, as well as listing subtotals (subdirectories).
A more powerful version of grep
The utility command grep has a more powerful brother that let us use POSIX Extended Regular Expressions.