DALLAS -- 7-Eleven Inc. will offer a free medium coffee to customers at participating U.S. and Canadian stores from 7 to 11 a.m. in their local time zones on Sept. 29. The giveaway is the convenience store chain's way of honoring National Coffee Day. Iced coffee is excluded from the deal.

Consumers looking for an opportunity to win a little 7-Eleven spending cash -- perhaps to use when they go to get their free cup of coffee -- can also take part in the retailer's "CofFREE Dip-A-Drip" event taking place a day earlier, Sept. 28, during the same hours.

To participate, 7-Eleven fans need to "Like" the retailer on Facebook. Then, from his or her Facebook page, the consumer will play a game where they attempt to "dip-a-drip" into a giant cup of 7-Eleven coffee. Those who successfully dip the drip will be eligible to win a $25 7-Eleven gift card.

Although the game will be controlled by consumers online, an actual dipping of a drip -- what 7-Eleven refers to as an "obnoxious person" -- into a giant cup of coffee will take place during a live event at Washington D.C.'s Union Station that same day.