Not all of these are healthy substitutes in my opinion, but some are, so use your own judgement. 20 Unique Healthy Food Alternatives --I'm interested to read about some of these things, and I know some of the substitutions only work in some circumstances.
Greek Yogurt Recipes - How To Use Greek Yogurt - Jeanette's Healthy Living - how to use Greek yogurt in cooking and baking, as a healthy substitute for sour cream, mayonnaise, heavy cream and cream cheese
You mix one ounce package of vanilla Greek yogurt, 2 tbsp peanut butter, 1 tbsp honey and a dash of cinnamon - this Dip makes about 5 Servings at 60 Calories each. Dip Apple Slices, Bananas, most any fruit or a healthy cracker!
Olive Oil Conversion Chart (use instead of butter or margarine). I see nothing wrong with using olive oil in the paleo diet. You pick olives off the trees, you squash them and you get olive oil - that's paleo.