One of my favorite ways to save money is to grow my own food (despite the fact that I live in an apartment) Plants don't need that much space to be super-productive, as long as you give them sufficient light, water, and nutrients
I usually have several plants of tomatoes, and go on a canning spree every summer. We only just used the last can of spaghetti sauce I made last year, we always seem to run out of that first oops. But I figure if a jar of tomato sauce costs around $2 (definitely more for organic, which is what mine mostly are) and we go through about 1 jar a week for 6 months, that's $50 saved right there, not to mention the barbecue sauce, sweet and sour sauce, and ketchup I also make from those tomatoes, PLUS not having to go to the grocery store more than every two weeks or less during the growing months, and all of the frozen zucchini, peas, beans, and more, that we stock up on from our garden. It adds up!
I just put my garden seeds into seedling pots a few days ago, and some are already coming up