Watch for people scanning prices with their phones on Saturday!

If you see an unusual number of people down at your local Target, Wal-Mart, or what-have-you-Mart scanning barcodes with their smartphones, they're probably using Amazon's Price Check app.  Why would they be doing this?  Well, this Saturday, Dec 10, Amazon will give you 5% off, up to $5 per item.  You can do this for up to three items, thus saving you up to $15!

Thanks to lifehacker for the info!