U.S. carriers' easy-to-use global services are fine for travelers looking for an emergency phone, or who won't make many calls while abroad, but travelers planning to make or receive a lot of calls should consider getting a local phone number abroad, which can deliver huge discounts.

Picking a World phone
World phones can be really cheap, but you'll have to shell out a bit for the best ones. Most of the following phones work with T-Mobile's and Cingular's systems even if purchased at independent retailers. AT&T and Nextel services only work with phones sold through those carriers, so we've recommended one phone for each of those services.

- Of the higher-priced world phones, the Sony Ericsson T68m ($499) is the world phone to have. It features seamless network switching, excellent battery life, a full-color screen, and a high-speed data modem for your laptop. The newer T200 is coming out this fall, but it lacks the color screen.

- If you tote a PDA, Handspring's Treo 270 smartphone ($499) is a compelling choice. The Treo has a tiny keyboard and flips open to a bright color screen. It seamlessly merges PDA, world phone, and e-mail.

- The Siemens S40 ($119) is our pick for a basic, inexpensive world phone. It's small, silvery, and stylish, and the backlit blue screen gives it a space-age feel.

- AT&T subscribers will want to nab the brand-new and very cool Siemens S46 ($150). It can access more kinds of digital networks than other phones, which means it will work in more countries and across more of the U.S. than any other model. It's also the only world phone that works in most of the rural U.S.

- The Nextel i2000plus ($125) is Nextel's only world phone that works in both the U.S. and overseas. The advantages are the same as all of Nextel's phones, including the snazzy "direct connect" walkie-talkie function, but this world phone could stand to be updated.