So as a continuation of making yogurt, we're going to learn how to process it into cheese. Yogurt Cheese is supposedly milder and can substitute for either sour cream or cream cheese. It's also fairly easy to make.
1) Take some cheesecloth and wrap a portion of your yogurt.
2) Rig this bunched-up cheesecloth so that it hangs suspended over a plastic bowl (I tied either end of my cheesecloth-package with string underneath the bowl)
3) Set in fridge (for milder cheese) or in an undisturbed place (for stronger cheese) for up to 48 hours.
The liquid that drips out is whey, and you're left with the cheese inside the cheesecloth. The whey can be a refreshing drink... remember little Miss Muffet who ate her curds (cheese curds) and whey (to drink)? Obviously her parents had lots of milk in the house and liked to process it into different edible things!
However just be careful you don't make the same mistake I did... I didn't suspend my cheese high enough above the bottom of the bowl... and a LOT of whey dripped down and the hanging cheese sat in the liquid, which completely defeated the whole purpose. So make sure it's a deep bowl and high cheese!