Everything works great. Except when it doesn't.

These days, tiny computers run your car, your house ... you name it. And fixes that once required a simple wrench now call for technical wizardry.

Nancy Morrison joined an elite group last year: She became the proud owner of a Toyota Prius. Those hybrid cars combine electric and gasoline engines to deliver amazing gas mileage -- often more than 50 miles per gallon.

But it takes a lot of technical wizardry to make the car run correctly. A computer controls just about everything, from the touch screens inside to how the gas and electric engines cooperate. You don't start the Prius; you boot it up.

Everything was going great for the Santa Cruz, Calif., resident until the day she drove the car just a mile too far. Despite a "low fuel" warning, Morrison ran the tank dry. The car stopped. But adding fuel couldn't get it to restart. It turns out her little oversight completely wiped out her car's memory. The entire software setup had to be reinstalled and configured. Other cars, like BMW's new 745, have been plagued by similar glitches, including fuel-system shutdowns while driving!

We expect our computers to crash; most of us have even learned the rudimentary steps to reboot them (which sometimes involves cursing a little). But these days, it's not just PCs that crash. Like an insidious infestation of termites, tiny computers now run just about everything that houses a motor. And wherever you have computers, you unfortunately get computer bugs. However, what's exasperating on your PC can be life-threatening elsewhere. It's difficult to reboot your car, for example, while galloping down the freeway at 65 mph (OK, maybe 70).

When software takes over your house, as my friend Cheryl Currid of Houston found out, it can be worse than termites. She installed a central computer that controls the lights, pipes TV and music into each room, and even secretly detects visitors, allowing her to either unlock or secure the house with a one-word command. A robot even mows the lawn. But the last time I visited, the house went haywire: Lights flashed on and off, the doorbell wouldn't work, and the TV was stuck on "Barney & Friends". Currid's hands were tied, she sighed: "It takes eight hours to restart my house."

Sure, none of us wants to live like that, but it's unavoidable. Computer software now lurks inside every new car and appliance we buy, and according to Chris Hall of repairclinic.com, a Web site that helps diagnose wayward appliances, it's only going to get worse: "Manufacturers are tripping over themselves to make appliances more innovative and tech-savvy."

Computers are even infiltrating the garden. I just tested a new sprinkler system that relies on a moisture-sensitive computer to decide when to water the grass. But what if a software glitch floods my lawn while I'm on vacation? My house could get washed away.

Despite the problems, computer-based features yield mostly better machines. Without high-tech parts, super-efficient electric and hybrid cars wouldn't exist. That sprinkler system can save lots of water, and the temperature and dirt sensors in computer-driven dishwashers mean you get cleaner stuff while using less energy. Even simple computer-controlled thermostats can save big money on your heating bill.

We can't stop software from invading our cars, appliances, yards and homes. But here are four easy steps to minimize problems:

1. Don't be the first to buy something. Sure, that new HammerFritzer 3000 looks great in the magazine, but remember: Pioneers are the ones with arrows in their backs. Take that newfangled BMW 745, for instance. Donald Buffamanti, chief sleuth for consumer watchdog group Auto Spies, says this year's model fixes a lot of problems that existed in last year's version 1.0.

2. Look for extended warranties. When it comes to hybrid cars, for example, a longer warranty is better because those essential batteries eventually will wear out. Bugs in computer-driven motors can take years to present themselves.

3. Don't throw away manuals. Software engineers put "failure codes" into their systems. That blinking number on your faulty stove or car can tell you exactly what's wrong -- if you can decipher the code. Can't find it? RepairClinic.com has compiled code listings for just about every appliance on the block.

And when worse comes to worse, at least you can unplug that appliance, or turn off your car. Wait a minute or so, and then plug it back in or turn it on. Shutting down power actually can exterminate a lot of bugs.

Oh, and take a lesson from Morrison: If your car requires service, get some -- and quickly. I've yet to see a computer that understands procrastination.

Contributing Editor Jim Louderback is editor in chief for Internet at Ziff Davis Media.