Received this catalina announcement with my purchase yesterday:

Buy Post Honey Bunches of Oats cereal between 4/24/09 and 5/17/09 and save on your next order:

Buy 3 and get $2 OYNO
Buy 4 and get $3 OYNO
Buy 5 or more and get $5 OYNO

All items must be purchased in one shopping order. Limited to product in stock.

(Honey bunches of oats honey roasted and with almonds are pictured so I assume it will be good on any variety.)