I make my own fat free buttermilk by simply adding some regular buttermilk
to skim milk and leaving it on the counter for a day (or overnight as the
case may be) until it curdles. It makes the best topping for baked
potatoes in my book. I just pour it over the potato.
You can also make a cream cheese substitute (I haven't tried cooking with
it). You merely place a container of ermilk into some boiling
water, turn off the heat and let the whole thing cool, pour off the liquid,
and refrigerate the 'cheese'. This is a common 'cheese' in Kiev, learned
from a friends immigrant relatives when the USSR finally allowed people to
leave that country.
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