Circle-K stores (Irving&#x27;s gas station convenience chain) used to do a deal where you&#x27;d get a free coffee every six or ten.<p>Most of the time, if you hit them in the morning, the cashier would just punch the whole card when you bought one...<p>It&#x27;s terrifying the amount of money you can save when you get in the habit of making your own coffee though.  It&#x27;s not quite on the level of movie popcorn, but it&#x27;s up there.