I often buy the grated parm packaged in the big square container at Costco (it costs about 16 dollars in my area), I noticed that the whole wedges of parm is about $13 dollars a pound, I decided to re-wash the container and grate the cheese into it. Voila! Saves me about 3 bucks.
I also use a plain Swiffer,but it still costs money to buy the refills. So my bright idea was to cut a microfiber cleaning cloth in half, use it as a dry wipe to dust, and than I wet it to mop. Whenever it gets too dirty, I just take it off, rinse it off and mop and when I'm done it goes into the laundry.
What's your odd way of saving?