Earlier this year, I posted here about my new love for going shampoo free in favor of baking soda and apple cider vinegar. It has been about 2 months, and I'm still a big fan. My hair is looking and feeling great, and seems to be growing faster.
Just wet your face, then rub a big pinch (about 1/4 t.) of baking soda all over your face, concentrating on any oily areas. Either rinse it off right away for normal cleaning, or keep it on as a mask for more of a deep clean and acne treatment. My husband has started using it too since going back to work in a kitchen, and it seems to really help minimize the inevitable breakouts.
Proactive scrub: $20/60 portions = $.3333
Baking Soda: $.70/403 (1/4 t.) portions = $.0017