Plant a garden. I am not sure how much money it really saves, but it sure is a nice release from the day-to-day stresses. It is also very rewarding to enjoy a vegetable (or fruit) that you helped to grow.
If you look around you can find some seeds for .10 (USD) a packet and they are usually pretty good. The only problem I had with these .10 packets was the head lettuce I planted turned out to be leaf. But it works just the same. - Submitted by Gryphan