You can't go wrong with a veggie or cheese tray. Buy what's on sale or in season at the supermarket, cut it up, arrange it nicely on a large plate and provide a variety of dips. Cheap and crowd-pleasing options always include baby carrots, broccoli, bell peppers, cauliflower, celery, sliced bananas, strawberries, pineapple and cantaloupe. For a finisher, favorites include ranch dressing, french onion dip, strawberry or pineapple fruit dip. For a sweeter treat, try chocolate dip.
Buy some large green and black olives and a few cans of sweet, dill and garlic pickles, and put out a relish tray.