We don't really think too much about it...
my car is paid for, if you are making car payments, sell those cars and buy one outright cash. Yeah, so what if it's 20 years old? You can find one with low mileage if you look hard enough and stay out of dealerships that will try to talk you into spending more money than you should.
DH rides his motorcycle to work if it isn't raining. this saves tons on gas money.
We don't eat steaks or pre-packaged food very often. It's amazing how much you can save on groceries if you're careful what you buy and how much you spend. If something non-perishable that we always use is on sale (toilet paper, coffee, whatever), I buy it whether we need it right then or not. Frozen dinners cost at least four times as much as the ingredients it would take to make the same meal. Dried beans are real real cheap and easy to make if you plan your meals ahead of time. If you eat meat, even the cheapest cuts are pretty tasty after stewing in the crockpot all day.
I quit smoking, that in itself was like a payraise! DH drinks store-brand soda instead of Coke now. little things really add up fast. Take a good look at what you are spending your money on. You should be able to see exactly where you can cut back.
there are the obvious ones, get rid of non-essential expenses. Every time I've called to cancel our satellite TV service, they have given me three months free. Call your creditors (I know you said you don't have credit card debt - you're already ahead!) and see if you can get lower interest rates. And, it sounds counter-productive, but pay as much extra on your debt as you possibly can each month, and make sure the extra goes to the principal. In just a year or two, you would be amazed at how much less you are paying in interest.
ETA - switching to cloth diapers saved us over $1000/year!