Cool photography tip to take pictures of the night sky with your iPhone: cover the lens and hold your finger on the screen until you see the “AE/AF LOCK” message. Now remove your fingers and take the picture. The lock gets released after you take the picture, so you have to do the two-finger thing each time.
Between the Sheets — Excel podcast episode 31: Excel’s secret DATEDIF function
A quick and simple way of finding the number of days, months or years between two dates is Excel’s secret DATEDIF function. When you type it in a worksheet, there’s no popup syntax help to indicate the function exists.