Money that you didn't think you had. Usually found in a time when you need it, making it a miracle to find.
Miracle money can most often be found in: back pocket, bottom of purse, small pockets in backpacks, between the seats in a car, under a mattress, in a bra.
"That will be $8.24."
"Shoot, I only have $7.12, let me see if I have any miracle money in my pockets."