NEW YORK (Fortune) -- Like the pioneering voice over Internet protocol (VoIP) phone service on which it is based, Vonage's new V-Phone is a bit quirky.

For starters, the V-Phone is a bright-orange thumb-sized USB drive that has no keypad for dialing numbers. It plugs into any broadband-enabled Windows-based PC - most likely a laptop - and automatically loads its own phone software onto the computer.

Vonage V-Phone: $40 plus monthly service at $15 to $25 a month.

Belkin Wi-Fi Phone for Skype

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If all goes well, a virtual phone keypad and address book pops up on the computer screen, and from then on the user can make or receive calls to any phone number over the Vonage (Charts) service, with unlimited calls anywhere in the United States and Canada and in several European countries, for a flat monthly fee of $25.

International rates to and from other countries are cheap (rate plan details can be found at www.vonage.com). Say you're traveling in Italy and want to call home. Just pull the V-Phone out of your pocket, jack in the earbud headphones with microphone, plug the V-Phone into your laptop or Internet café PC, and type the number you want to call. It's a local call.

What problems I had with the V-Phone arose from Windows. The V-Phone software is supposed to run automatically, but it did so only about half the time on a brand-new Windows computer, and occasionally it crashed, though never in the middle of a call. Fixing the problem simply involved unplugging the V-Phone from the USB port, waiting ten seconds, and reinserting it.

Voice calls were loud and clear, albeit with a faint Internet-induced echo. If people call you when your laptop is shut down, calls go either to a voice mailbox or, if you choose, to another phone number of your choice.

For those willing to put up with its quirks - a group that probably includes global road warriors who are interested in a cheap phone service that goes anywhere there's a high-speed Internet connection - the new V-Phone is a clever, portable tool.

For cheap - or even free - domestic and international calling without booting up a PC, Belkin's Wi-Fi Phone for Skype is a novel alternative. The candy bar-style phone uses any available Wi-Fi-compatible Internet connection to make or receive calls using the Skype VoIP service (www.skype.com).

If you've got a Wi-Fi setup at home, the Belkin phone allows Skype calling wherever there's a good signal, not just near your PC. It works well on the road, too, anywhere there's a public Wi-Fi hot spot.

More and more cities are experimenting with municipal Wi-Fi, but until the service is ubiquitous, the Belkin phone will be a niche device. On the other hand, if you often travel overseas to lands where your own cell phone does not work, the Belkin phone could be a great alternative.

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