Grease cookie sheets; preheat oven to 350 degrees. With electric mixer, beat butter until creamy, gradually beating in sugar. Add vanilla. On sheet of foil, stir together flour and salt; add to butter mixture, blending well. Form dough into 1 inch balls. If too soft, refrigerate dough for 2 hours. Roll in flaked coconut and place on prepared cookie sheets. Bake 8-10 minutes or until lightly browned.