(MONEY Magazine) – If you tend to drive above the speed limit, hit the brakes before you get hit in the wallet this summer. Speeding fines are accelerating at a frightening pace. Just ask all-American talk-show host David Letterman. After getting nabbed four times in his home state of Connecticut between 1987 and '89 and losing his license for 30 days, he got whacked with a splashy $275 fine in New York last September for gunning his red Dodge Stealth 78 mph in a 55-mph zone (luckily a judge subsequently reduced the fine to $125). What does Dave's imitation of Mario Andretti have to do with you? Just this. Letterman, who reportedly makes $12.5 million a year, can laugh off his costly tickets. (He even got his mother to appeal to Hillary Clinton on the air!) But if you speed from time to time -- as one out of every two Americans does -- and get caught, you'll find yourself grimly facing fines that, in many cases, have climbed 50% to 100% since 1990. "Most states are in budgetary difficulty, so more and more are adding surcharges to speeding tickets to bolster revenue," says Jim Baxter, president of the National Motorists Association (800-882-2785), a drivers rights group in Dane, Wis. In Rhode Island, for example, a ticket that cost $35 in 1987 when the state began slapping special assessments on speeders can cost $200 today, counting add-ons for things like substance-abuse programs and emergency medical services. State assemblyman Louis Caldera of California, where assessments for everything from DNA identification to child-abuse counseling can inflate a $100 basic fine into a $270 ticket, adds: "It's tremendously unfair." It's also tremendously confusing. Fines vary wildly from state to state --from Connecticut's top national average tab of $200 down to just $5 in Montana (see the table at right). Last fall, Seattle restaurant manager Dalena Small, 24, was ticketed twice for driving 75 mph on a cross-country vacation, once in South Dakota ($68) and once in Connecticut ($200). "Obviously, Connecticut is using drivers to bail out its budget," Small says angrily. What's worse, your costs don't stop there. Speeding tickets can hike your insurance rates dramatically. For instance, a New Jersey driver with an unblemished record pays an average of $807 a year for full-coverage auto insurance. If he or she picks up two points -- the standard penalty with each conviction for exceeding New Jersey's speed limit by as little as 1 mph -- State Farm, for example, would hike that driver's rate by 27%, or $220. With four points, the annual premium rises by $425; and with eight, it's $900, for a grand total of $1,707. Furthermore, the points -- and the higher premiums -- stay in force for three years. When you're pulled over, don't volunteer anything that can be used against you in court. Also, if you do get ticketed, you can fight back. "Speeding tickets are often worth contesting if they say you were going less than 10 miles or so over the limit on a road other than a major highway -- or if you know you weren't going as fast as the officer claims," according to David | Brown, a Monterey, Calif. attorney and author of Fight Your Ticket (Nolo, $18.95). Even if you push the posted limit, you can sometimes get off in court by arguing that there was little traffic and you were driving in a safe manner. Other tips: Plead not guilty (then the prosecution must prove every element of its case); or request a jury trial in states where that's possible (juries are often more sympathetic to drivers than judges). Or pray that the officer doesn't show up in court, which Brown estimates happens about a third of the time; usually your case gets dismissed. Of course, if you get caught while driving through a state and don't want to wait around for a trial, just pay the darned ticket.

CHART: NOT AVAILABLE CREDIT: Sources: October 1993 National Motorists Association survey; American Automobile Association; state officials CAPTION: TICKET FINES: FROM $200 TO $5 Here's what the average ticket costs if you get caught driving up to 15 mph over the limit. The fines range from Connecticut's stiff $200 down to Montana's puny $5.