Great ideas on this thread! I love it so I thought I'd share what I've been doing to cut costs, keep costs down, and be generally frugal.
I got a few chickens and am waiting for them to grow up and start laying. I plan to increase my little flock in the future (year or so) to allow for dual purpose.
I buy in bulk where I can, mainly staples like flour, sugar, rice, etc... . Space is an issue for me so I can only get so much at a time but I haven't bought flour in a year. It's well sealed so I'm not too worried. I used to grocery shop the sales and coupon way but it was harder to keep up with and didn't always meet my needs.
About once a week or so, I go through the kitchen and do an inventory, put it in an excel worksheet that now I only have to update. Every week I plan the menu right down to the snacks, compare it to the inventory and shop accordingly.
I've started cooking smaller meals to cut down on the amount of leftovers being thrown out. Everyone still gets fed but there's nothing left in the pot; if there is, it's not much and it sometimes gets eaten. Better than wasting 2x as much though.
I don't drive much. Heck, I don't even get out much. I have a 4Runner and it was filled up well over 2 weeks ago and I've got about 1/4 to last me till next week, which is plenty. I drive to the grocery store, school, and down the street to the pre-school. I could probably walk to the preschool but its on the way to my school too. I have thought about getting a bike that I could take for short trips (under 2 miles) instead of driving but I've got little one with me too so it won't work.
I don't eat out often and when I do I spend less than $5. Most of the time.
I will not go without A/C. No way, no how. I'm in southern Louisiana. That's explanation enough.

I have always been interested in making my own detergent and softener but am slightly discouraged by my family. They just don't get it I guess. I think I'm going to try it anyway.
As for $$, I figure up the minimum for me to spend that week and hide the rest. Anything left at the end of the week goes in a jar. Even if its a $20. I have been amazed at how much I rack up in a few months time. I also find that I can survive with a lot less than I thought.