If you're not from the U.S., you'll be appalled at the poor reach of the GSM (Global System for Mobile Communications) wireless network, which is used by much of the rest of the world. Your phone will probably work in most major U.S. cities; it definitely won't work in many rural areas. To see where GSM phones work in the U.S., check out www.t-mobile.com/coverage. And you may or may not be able to send SMS (text messaging) home.

If you need to stay in touch at a destination where you know your phone won't work, rent a phone that does from InTouch USA (tel. 800/872-7626; www.intouchglobal.com) or a rental car location, but beware that you'll pay $1 a minute or more for airtime. Also consider buying a cheap pay-as-you-go phone in the city/region where you are staying.

If you're venturing deep into national parks, you may want to consider renting a satellite phone ("satphone"). It's different from a cellphone, in that it connects to satellites rather than ground-based towers. Unfortunately, you'll pay at least $2 per minute to use the phone, and it works only where you can see the horizon (that is, usually not indoors). In North America, you can rent Iridium satellite phones from RoadPost (www.roadpost.com; tel. 888/290-1606 or 905/272-5665). InTouch USA offers a wider range of satphones but at higher rates.

Voice-Over Internet Protocol (VOIP)

If you have Web access while traveling, consider a broadband-based telephone service (in technical terms, Voice-over Internet protocol, or VoIP) such as Skype (www.skype.com) or Vonage (www.vonage.com), which allow you to make free international calls from your laptop or in a cybercafe. Neither service requires the people you're calling to also have that service (though there are fees if they do not). Check the websites for details.

Internet & E-Mail

With Your Own Computer -- To find public Wi-Fi hotspots at your destination, go to www.jiwire.com; its Hotspot Finder holds the world's largest directory of public wireless hotspots.

Aside from cybercafes, most public libraries in the United States offer Internet access free or for a small charge.

Most business-class hotels in the U.S. offer Wi-Fi or broadband Internet access (but check to see what the daily rate is).

Without Your Own Computer -- Most major airports have Internet kiosks that provide basic Web access for a per-minute fee that's usually higher than cybercafe prices. Check out copy shops like Kinko's (FedEx Kinkos), which offers computer stations with fully loaded software (as well as Wi-Fi).

You'll also find cybercafes in most big cities and around university campuses; many hotels offer Internet access (sometimes for a fee) at terminals in their lobbies or business centers.

Online Traveler's Toolbox -- Veteran travelers usually carry some essential items to make their trips easier. Following is a selection of handy online tools to bookmark and use.

  • Airplane Food (www.airlinemeals.net)
  • Airplane Seating (www.seatguru.com and www.airlinequality.com)
  • Foreign Languages for Travelers (www.travlang.com)
  • Maps (www.mapquest.com)
  • Subway Navigator (www.subwaynavigator.com)
  • Time and Date (www.timeanddate.com)
  • Travel Warnings (http://travel.state.gov, www.fco.gov.uk/travel, www.voyage.gc.ca, www.smartraveller.gov.au)
  • Universal Currency Converter (www.oanda.com)
  • Weather (www.intellicast.com and www.weather.com)

Note: This information was accurate when it was published, but can change without notice. Please be sure to confirm all rates and details directly with the companies in question before planning your trip.