I have committed to donating $3 of grocery purchases to a local food bank each week.

Here's what I'll be giving this week:

8 cans Dole pineapple
1 tube Colgate toothpaste
10 boxes Mueller's pasta

All purchases at Publix, prices good through Christmas Eve.
The pasta was on sale BOGO with $.55 coupon per box, total for 10 boxes was $.35
Toothpaste was on sale for $1, with $.75 coupon paid $.25 per tube
Dole pineapples were BOGO with $1/2 cans coupon, total for 8 cans was $2.40

I haven't been able to do this weekly as I'd hoped.  Part of the excuse for that is that I don't do serious grocery shopping every week -- though that's something I'm working to change (it's not always easy to find the time to clip coupons, find deals, print coupons, organize coupons with lists, and then go to the store).