Travelers abroad can now avoid pricey international mobile roaming charges—if they are willing to pack some extra hardware.

Voice-Over Internet Protocol Service (VOIP) is a technology that breaks up voice signals into data packets and sends them over the Internet. Because it bypasses expensive phone lines, VOIP service is cheaper for providers and the consumer.

Major cable and phone companies such as Time Warner and Verizon plan to roll out VOIP to homes across the country this year, but travelers can already benefit from VOIP services offered by a handful of providers, including Vonage ( and 8x8's Packet8 ( Both offer overseas service that can be used overseas atU.S. dialing rates. All you need is a high-speed Internet connection (which can be found in many luxury hotels around the world), plus a little black box (supplied by VOIP providers). The box plugs into a network on one side and a telephone on the other, and allows you to take your home phone number with you wherever you go.

Vonage's plans for calls to anywhere in the United States and Canada range from $15 a month for 500 calling minutes to $35 for unlimited calling. Packet8's cheapest plan has an even lower rate: $19.95 a month for unlimited calling to the U.S.A. and Canada. (Vonage and Packet8 customers don't pay additional charges when calling to the States or Canada from abroad, but they do pay extra for international calls made from the United States or abroad.)

Skype (, a European company created by the entrepreneurs behind the file-sharing site Kazaa, is another VOIP service that allows travelers to make calls from foreign locations. But—unlike Vonage or Packet8—users on both ends of the line must be Skype customers. The upside is that it's free: the service can be downloaded from the company's Web site.