Are you tired of your notebook running out of power away from a wall wart? We're looking at three universal adapters able to get your battery charged again, whether you're on the road, in the air, or sitting down next to an AC plug.

If you consider yourself to be a road warrior, you need a way to keep your notebook running when when you're away from a wall socket. And that's regardless of whether your primary battery has the chops to keep you operational all day long. Put simply, most folks can't count on a day's worth of up-time. So, it's important to have a solution in place for putting a bit of pep back into your mobile platform during your afternoon siesta.

What do you need in order to keep your notebook fully functional? If you're in a car or on a plane, you need a cigarette lighter receptacle or an EmPower plug, along with a compatible power adapter. Most system vendors (like Dell and Lenovo) offer travel adapters, but they can get pretty expensive. Worse, they aren’t always compatible with multiple generations of products.

For example, when IBM moved from 16 V to 19 V, timed to coincide with Intel's Pentium-M to Core 2 Duo transition, the company adopted a different plug size. That meant the older AC/DC combo adapter (P/N: 73P4502) wouldn't work with the newer hardware. Owners of more recent Lenovo notebooks can use the current AC/DC combo adapter will find that it's backward compatible through the use of a different plug tip.

Traveling Headaches

If you travel overseas, you probably use plug adapters as well, since AC sockets differ from one region to the next. Currently, most system vendors arm their mobile offerings with 110-240 V power adapters, which means that they're universally compatible, so long as you have the right wall connector. A notebook sold in the U.S. might include the same power brick as one in Europe, but they two systems will come with different power cords.

If you're traveling abroad with a power adapter that isn't 110-240 V-capable, there's a good chance you need a voltage converter or an entirely new brick, depending on where you're going. Travel adapter kits for cars and trains cost up to $100. So, if you aren't interested in making that investment, a power inverter is your only other course of action. Planes are another matter entirely.

There is no universal power plug standard used within the travel industry. Even in a single airline's fleet, the same model of plan might use different plugs depending on its configuration. For example, there are four different 737 configurations flown by Alaskan Airlines; one uses cigarette lighter receptacles and one employs the EmPower connector.