by Amanda Gengler
Cut out some waste and take advantage of a few overlooked deals, and you can rein in your budget without feeling like a penny-pincher.
1. Gas - Conserve Fuel in Any Car
5% of your household budget, up 21% from a year ago
Underinflated tires can cut your mileage per gallon by 5%, says Jesse Toprak of Edmunds.com. Check your tires once a month.
And lose the lead foot: You can save up to 33% by maintaining steadier, slower speeds.
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Potential savings: About $800 a year - not to mention what you'll save in speeding tickets.
2. Gas - Take Advantage of Your Credit Card
If you pay in full each month, pick one, like Chase Freedom, that gives cash back on gas.
Forget it if you carry a balance: Rewards cards usually charge higher rates.
Potential savings: Up to $200 a year
3. Gas - Get Rid of the Guzzler
Making your next car a hybrid could triple your mileage per gallon. If gas stays above $3.60, a Toyota Camry hybrid makes up for its premium over the standard model in a year and a half.
Even if you don't go hybrid, choosing the most fuel-efficient vehicle in your car class can still save $200 to $1,500 a year in fuel costs.
To compare the true fuel cost for all 2008 models, go to edmunds.com or fueleconomy.gov.
Potential savings: $2,400 a year if you trade an SUV for a hybrid
4. Food - Learn Stupid Supermarket Tricks
14% of your household budget
Up 5% from a year ago
Stores use all kinds of marketing ploys to get you to buy more than you ever intended. "The supermarket is set up so that you will buy on impulse," says Marion Nestle, author of "What to Eat." The more you see, the more you purchase.
That's why they make you march all the way to the back to buy milk and they keep the aisles long and unbroken. So bring a list and stick to it, and never shop when hungry or tired, as you'll find it harder to resist temptation.
And search high and low. "The cheapest items are often on the top and bottom shelves, since companies pay for prime space on middle shelves and aisle ends," says Paco Underhill, author of "Why We Buy."
Potential savings: Up to $1,200 from cutting out just half of unplanned purchases
5. Food - Know When to Stock Up
You can get a weekly list of items going on sale at your local store, including sales that aren't advertised, at thegrocerygame.com.
The service costs $1 for a four-week trial or $10 for an eight-week subscription. Buy in bulk when deep discounts are on.
Potential savings: More than $1,000 a year
6. Food - A Little Home Cooking
Putting a homemade meal on the table five to seven nights a week the way your mother did may seem daunting.
In the new age of the Food Network and Williams-Sonoma, lots of moms and dads know how to whip up a mean saffron risotto for a Sunday night but never got the knack for the day-to-day basics.
To bone up on your home ec, check out Mitchell Davis' "Kitchen Sense" and Mark Bittman's "How to Cook Everything," which are loaded with recipes for quick and simple meals.
If you plan entrées with overlapping ingredients and buy everything for the week at once, you can not only save money but, often, put a dinner together in the time it would take to pick up takeout.
Potential savings: $50 a month
7. Home Energy - Seal Up Your House
4% of your household budget
Up 9% from a year ago
To find air leaks, conduct a home-energy audit following the instructions at energystar.gov or hire a pro to do it for $200 and up.
You can cut up to 25% of your heating and cooling costs by adding insulation and using caulk, spray foam and weatherstripping to seal leaks around windows and doors and in attics and basements.
Potential savings: $1,375 in five years, after materials
8. Home Energy - Get Efficient
Install an Energy Star programmable thermostat for $60 to turn down the heat when you sleep and raise it in the morning. (This makes climbing out of bed easier too.)
Be sure to change the air filter in your heating and cooling system at least every three months.
Potential savings: $220 a year
9. Home Energy - Slay the Vampires
So-called vampire appliances suck electricity even when you aren't using them.
Plug devices with standby power, such as TVs and stereos, into a power strip so you can turn them all off at once. (Some have timers to switch off at night.)
To further cut your electric bill, replace regular bulbs with compact fluorescents.
Potential savings: More than $300 over five years
10. College - Contribute to a 529 Plan Early and Often
1% of your household budget
Up 6% from a year ago
These state-sponsored plans let you exclude your college-savings earnings from federal and state taxes. Says Mark Kantrowitz of FinAid.org: "The long-run return, with the tax savings, typically exceeds the normal 6% to 8% yearly tuition increase."
For calculators to estimate your total costs, as well as details about your state's 529, go to finaid.org and savingforcollege.com. To find out how much a school will cost, use the calculator to the right.
If your local plan charges more than 0.5% a year, consider another state's. (Note that you might lose a state tax deduction on contributions, but this is sometimes worth it.)
Opt for an Illinois or Ohio direct program - both offer investments with low fees and strong management.
Potential savings: About $5,000 in tax savings over 10 years
11. College - Max Out Cheap Federal Aid First
Before applying for any private loans, take out the maximum in federal, typically Stafford, loans. Their fixed rates - 6% to 6.8% - are generally less than private lenders' variable rates.
After you tap out Staffords, federal parent PLUS loans are generally the best deal.
Potential savings: $8,000 on $27,000 in loans in 10 years
12. Medical Costs - Choose Your Deductible Wisely
6% of your household budget
Up 4% from a year ago
If your company gives you a choice, you may be tempted by the lower premium on a high-deductible health plan.
These work for some people, but you face more financial risk if you get sick, and you may have to pay full price for most prescriptions until you meet the deductible.
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High-deductible plans are generally best for younger people without health problems; others should stick with traditional plans.
Potential savings: High-deductible plans could save you $750 a year in premiums. But if you get seriously ill, a traditional plan could mean thousands less in bills.
13. Medical Costs - Don't Pay Taxes You Don't Have To
If you have a qualifying high-deductible health plan, make sure to contribute to a health savings account to fund your current and future medical bills.
If you have a traditional plan and your employer offers a flexible spending account, sign up. It lets you use untaxed salary to pay for many out-of-pocket health expenses.
Potential savings: About $280 for every $1,000 set aside
14. Medical Costs - Don't Be Afraid to Haggle
If you go out of network or are in a high-deductible health plan, ask the doctor for a discount.
You can get an idea of reasonable prices at your insurer's website or, for an $8 fee, at healthgrades.com.
One poll says that 60% of patients who negotiate with a doctor succeed. Your best bet: Offer to pay up front in cash.
Potential savings: $85 for a specialist consultation
And don't forget...
A dollar saved is a dollar saved, so you should look to trim any needless cost, even on goods not jumping in price. Here are four easy ways to find extra money you didn't even know you were spending.
15. Ask your credit-card issuer if you can get a lower rate.
16. Don't use all your minutes? Change cell plans.
17. Look at your insurance. You may want to lower the premium for your car insurance, for example, by raising your deductible.
18. If you really aren't going to the gym anymore or those Netflix envelopes sit there unopened, stop putting off the inevitable: Cancel.