In a large bowl, cream together the margarine, brown sugar and white sugar until smooth. Beat in the eggs one at a time, mixing well after each addition.
Sift together the flour, bicarb soda, baking powder and salt; stir into the creamed mixture until just blended. Mix in the Cornflakes, rolled oats, coconut and chocolate chips. Drop by heaping spoonfuls onto ungreased baking trays.
Bake for 8 to 10 minutes in the preheated oven, or until edges are lightly browned. Cool on wire racks.