I found a great command today, using linux bash shell and I got enthusiast. You can get printed a calendar in your shell giving you highlighted the current date.
Just type cal in a shell.
If you want to print the calendar for an other month than the current just tell it to do it passing an argument -m and the number of the month or the First 3 letters of the month.
$cal -m 01
$cal -m Jul
I found this command very useful!