I got this lovely and simple recipe from someone on the Microbial Nutrition yahoo list; it's tasty, like crunchy apple pie filling. :)
7-8 lg. tart apples, cored/peeled/sliced into 1/4"x1" pieces
1/2 cup whey
2 T. pumpkin pie spice (about 4 tsp. cinnamon, 1.5 tsp. ginger, 1/4 tsp. nutmeg and 1/4 tsp. cloves)
1 tsp. vanilla extract
1 T. salt dissolved in 2 cups hot water, then cooled; more water to cover, as needed
Toss apples and spices together until thoroughly mixed; add whey and mix again.
Pack the apples into a 2- or 3-liter jar, cover with brine and enough water to cover, and let ferment at room temperature for 5-7 days (I used a Fido jar; you might have to be careful to ensure that the apples stay submerged otherwise).
This created a sweet ferment, with a tiny tangy aftertaste and a ropy cinnamon "sauce". Very interesting!