I know what you mean Ripliancum. Pickles, mustards, sauces, preservers, relishes, chutney, spreads etc etc I love them all. Going to fairs and local markets are a lesson in temptation with all the delicious jars up for sampling and purchase.
They are the things that round out a kitchen after your two other main ingredient categories; staples (dry goods, milk, yoghurt etc) and flavourings (spices, herbs etc). Nothing better than some bread, some cheese (generally a nice sharp cheddar), a selection of cold cuts and a selection of condiments.
Currently going through a Piccalilli phase (the traditional English mustard pickled vegetables), it's absolutely delicious. Also the Chinese hoi sin sauce is great either included in a dish or as a sauce served on the side.