Alton Brown did this on Good Eats. I've meant to try it, but have not gotten around to it. I like CC. IIRC Alton used leftover milk from something else, or visa versa.
I think his recipe was simply some vinegar in skim milk or something like that. Maybe it was lemon Juice...
If your takin' your girlfriend out tonight
You better park the car well out of sight
'Cos if they catch you in the back seat trying to pick her locks
They're gonna send you back to mother in a cardboard box !