If you're hip to how much corn syrup is in our foods, DIY ketchup might be appealing in itself. Knowing that you can tweak its flavour hundreds of ways with your own sauces, spices and sweeteners just seals the deal.
DIY site Instructables has a very thoughtful, well-photographed step-by-step on making your own ketchup (or catsup, if you prefer). Author scoochmaroo has a pretty neat recipe that uses allspice and molasses, but you can switch up any of his ingredients for your own preferences, as long as you keep with the basic ratio of tomato paste to water. After simmering in a pot for a few hours and reaching the right consistency, you bottle your good stuff, and then really enjoy the heck out of some homemade fries.