Thanks to Ethan's mom for this Frugal Baby Tip!
My pediatrician recommended dabbing on a little of the same type of OTC yeast infection cream you'd use on yourself (Miconazole 7, etc.) to cure this type of diaper rash (red and raw roundish patches, and peeling skin in creases). In the couple instances we had of this rash, it was gone within a day or two of using this cream. Certainly not free, but works quickly with just a few applications and without any odor.