Chill a highball glass. Swirl around 1 oz of Anisette (Herbsaint will do nicely). Add 1 oz Light Rum (Your choice) Fill with 7 Up (or carbonated water and lime and a splash of simple syrup). Add ice if you like.
The Swordfish was devised upon reflection on the Hammerhead cocktail. As we were bloody well out of Coca Cola and hadn't any Sambucca; the obvious solution involved substituting 7 Up and Herbsainte. Col. Picketsmithe of the Municpal Forces of Fondeline remarked that it was perhaps a little like drinking liquid licorice, to which I responded with a firm handed slap upon his mustachioed countenance. Pip Pip!