Fermented veggies (home made or bough, sauerkraut being the most popular)
Home made is really easy and less expensive, although it can be difficult to prepare all that cabbage, some other veggies are easier (grated daikon, grated carrots, pickled relish) etc. Nourishing Tradition is a book written by Sally Fallon with many recipes for pickled food, and you can find them on the internet, or you have to improvise by comparing with a sauerkraut recipe. Just stay away from the stupid recipes that involve a lot of vinegar, usually it is simply veggie, water, Sea Salt and a starter culture (usually not even necessary but a lot of better if you don't want to miss any batches).