"Hey, let's go to Walgreens, I have this Register Reward that's expiring."
(wander around Wags for 40 minutes trying to find a way to roll it, and finding none, then attempting to find something to blow it on)
Cashier Boy: "You saved pretty well on this."
"Well, yea, I had to use my RR before it expired."
"Oh, that coupon didn't expire until the 7th."
I was crushed. It could have been the perfect start to rolling the Crest RR. Grrrr. I am a sad, sad, girl.