Keep an eye out for specially-marked Kellogg's cereal boxes. They contain multiple $1 off coupons. You'll find them in the following cereals:
Nutri-Grain Cereal Bars
This week Target has some Kelloggs cereal for 4/$10. One box of Rice Krispies I bought had the coupons in it. Also, this week at Target, if you buy 4 boxes you get a $5 gift card to use on a future purchase. Target sale is good thru Saturday.