Neat site!!
I make my own Vanilla Extract, self rising flour and buttermilk. We don't use buttermilk enough to keep a quart sized carton in the fridge. And making self rising flour myself tastes better than the already packaged version (my biscuits are fluffier).
One day I may experiment with making coconut, almond, orange as well lemon extracts one day.
The butter one looks easy enough and I have the ingredients already.