Black Friday — the Friday after Thanksgiving — is traditionally the biggest shopping day of the year, with retailers offering extrraordinary price reductions to help fuel holiday spending. Apple has posted a teaser on their website inviting shoppers to stop by for a one-day sale on Friday. The teaser reads: "Mark your calendar now, and come back to the Apple Online Store the day after Thanksgiving for the special one-day event. You’ll discover amazing iPad, iPod, and Mac gifts for everyone on your list." Odd that it doesn't mention the iPhone.