We saved more than 50% on our car insurance by switching to AARP's insurance. Recently we realized that we don't really watch tv all that much, so had the cable company switch us to their economy plan. Funny thing is that they dont even tell you about that plan, a friend of our accidently found it hidden in a pdf on their website.
Even tho the kids have grown and gone and its just me and hubby at home, we still shop for food in bulk at sam's club. I tend to stock up on their meat when its marked down and repackage it into smaller portions and freeze. Pet food, laundry soap, toilet paper, cleaning supplies etc etc are all cheaper when bought in bulk sizes.
We are good about eating leftovers instead of letting them go to waste. We sometimes eat them for lunch, and sometimes they get remade into a different meal for another dinner.
A huge savings for us recently was switching over to the "time of use" program at the power company. I realize that this plan would not work well for everyone, but it has cut our yearly power bill average by about half.