There used to be a really handy terminal command to open debug mode in iCal. One of my favorite settings was the ability to display two weeks in week view. Unfortunately, the command stopped working in Mountain Lion and it doesn't appear anyone has figured out how to resurrect it. (I tried for 30 minutes.)

In the meantime, there is a terminal command to set the number of days to display in week view. Mac OS X Hints shows the way but here it is.

defaults write com.apple.iCal CalUIDebugDefaultDaysInWeekView XX

Substitute the number of days for XX. If that blows your mind, run it again and change the number back to 7.

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