Treat Receipt

Great marketing idea I experienced at Starbucks:  Yesterday, we met over coffee with a new contact in the non-profit marketing industry, and as I was paying the cashier asked if I wanted my "receipt for later."  I thought she was a genius because she knew I was planning to write off this overpriced coffee, but realized it's a clever marketing ploy.  She stamped the receipt and handed it back to me, and it read " TREAT RECEIPT:  Bring this in after 2 p.m. today and get any grande cold drink for just $2 (plus tax)."  What a great way to get customers to return during the slow hours!  And my favorite part, is that it's a cheap tool- that stamp probably cost less than a blueberry muffin and from there it's word of mouth.  Wizardry, once again.