Today I saved money by using rainwater for my laundry and then by reusing the grey water in my garden.
I received a free gallon of garden compost tea from my hydroponics store by bringing them a coupon that came in the mail. I also gave them 10 empty milk containers (you get a free gallon of tea for every 50 milk jugs - I knew I was saving them for a reason!)

One gallon of professionally brewed compost tea makes 5 gallons of garden fertilizer BTW.
I got several large bins of free mulch from my neighborhood landscape company. I try to add a few bins a day to my weedy yard to make a mulch. Some goes right into the garden and composter too.
I also had a free hot meal at my food bank and got two free boxes of food plus several bags of misc free produce.
I brought in some slightly rotten produce that was leftover at the food food bank to my friend with a goat and got a quart of free raw goat milk for my kitten.