1) My plastic bag dryer from reusablebags. I use this everyday to dry ziploc bags after washing so, I can reuse them and for drying reusable water bottles that I pack in my sons lunch.
2) A clean/dirty homemade magnet for my dishwasher. I made this by using one of those free picture frame magnets and a piece of paper that says clean on one side and dirty on the other. I love this because my son (he puts up the dishes) knows when they are ready to be put up. This saves me from rewashing them.
3) My foaming soap dispenser. I put whatever soap I have on hand (usually that I got free) in there and add water. This cuts back on spending $$ on expensive hand soap.
4) My crockpot. I can cook a whole chicken or roast in there, then use it for 2-3 meals. I can also save on dishes by not using 3-4 pans.
5) My menu plan. I have a calendar that I use to plan my meals for the month which saves me a ton of $$.Check out http://lifeasmom.com/ for some of her ideas to save $$$.