Yes, I have found them in many wonderful places. The obvious ones are the car, the floor (all over the house - even in rooms where she isn't allowed), the bottom of the diaper bag, and my purse. But, I have found one in my bra when undressing for the day. I think I must have been really tired that day not to notice that little circle of starch being melded in there.
I am convinced that someday, when our civilization is long gone, archeologists will come along and find bunches and bunches of Cheerios. I wonder what their explanation will be.