Put the pasta in a pot of salted water on medium heat. During this time, prepare the sauce, in a deep frying pan in the oil fry the onion and the skinless sausages (can be replaced with ham, if you do not like skinless sausages). When the gain slightly golden pour tomato juice and stir to not burn, does not have to flow all the water from the sap. During this time, cut the two types of feta cheese cubes. And add them to the sauce and do not stop stirring to not become lumpy cheese will melt and the sauce will thicken. Cut the olives and add them (easier if you take pitted olives), also savory and can sprinkle a little pepper. All the time stirring the sauce to not burn and not become too thick or lumpy. When the sauce is ready you can download it from the heat, waiting to boil spaghetti, if they are not ready. When everything is ready, distribute the pasta in portions, seasoning top with sauce and serve the dish. * All ingredients for the sauce is replaceable, if you do not like something from the above. * For your convenience can cut all the products for the sauce in advance, as must constantly stir it does not become lumps of cheese.