It drives my husband crazy but I save all my receipts from my grocery trips. I realized I was missing out on opportunities for Mail in Rebates because I had purchased the items last week and thrown away my receipt.
Luckily, I began to save all my receipts and put them in a basket for later use. This morning I filled out 2 mail in rebates for items I've purchased in the last month but didn't know the rebates existed. It may take 8-10 weeks but I will have 2 checks coming to me in the mail!
Check out some rebate offers here.