I make an easy one - steam or boil taters, cool completely.
Add chopped celery, onion (optional), hard-cooked eggs, chopped sweet pickles or sweet pickle relish, mayo or salad dressing and sometimes a dab of yellow mustard.
Of course, at times and depending on who I was feeding, maybe minced red sweet pepper, minced carrot or - instead of mayo/salad dressing - olive oil and vinegar - season with salt and pepper.