In the past 2 weeks, I've tried two new sandwiches that made it worthy to start a thread.
Just finished the Arby's Black Angus Sandwich. Best thing on their menu.

Last time I ate out was Burger King (which I'm not a fan of). I tried their BK Stuffed Steakhouse. It was also fantastic and the only reason why I'll go back.

What fast food sammiches are "damn good sammiches" for you?