We like Yogurt Cheese.
You can get this nifty little thing called a "Yogurt Cheese Maker" from one of my favorite stores, BreadBeckers.com.
You add plain yogurt, let it drain and thicken and you have a yummy replacement for mayo, cream cheese and sour cream. Control the amount of drainage for the desired consistency.
We love it on homemade bread with sliced strawberries.
They even have whole cookbooks for the stuff!

I find mayo to be one of the most disgusting food products on the market. I watched a food processor demonstration on making your own mayo when I was working in a department store in college 30 years ago. The ingredients were...cooking oil, an egg or two, pepper and more cooking oil. I already knew it was nasty but had no idea how bad it was until that day.