Hold the phone — this one fits slot in laptop

There are literally dozens of Internet phone services these days.

The idea behind the technology of these phones — voice over Internet Protocol, or VoIP — is fairly simply to understand but highly complex to make happen. I still don't think it's ready for prime time, but it's getting better.

So what do you need to be able to use your computer to make phone calls? For the most part, all you need is a fast connection to the Internet and the VoIP software. At the very least, that will let you make computer-to-computer voice connections.

Other than the cost of your Internet service, that setup lets you make unlimited voice calls to anywhere at no charge. The VoIP software that makes this happen — Skype is a perfect example — is typically free.

The problem with this kind of connection is that either you need to set up your connections in advance or the computer user you are calling must know to leave the receiving computer on so it can take your calls.

Connection fee

If you want to use your computer to call an actual telephone, there's typically some kind of connection fee. Again, this varies greatly depending on the VoIP service you choose.

And if someone wants to call you, your computer had better be turned on or they'll get something equivalent to a voicemail telling them to leave their name and number.

I've seen a cornucopia of devices that let you use VoIP, starting with a simple mic and speaker setup.

Then there are headsets with a built-in microphone that's positioned near your mouth, speakerphones for hands-free talking, and even complete telephone handsets that connect directly to your computer's USB port. But none of these are as clever or as cool as the Vo200 Bluetooth Internet Phone being offered by Kensington (www.kensington.com).

Most portable computers have a small PCMCIA slot that's about the size of a business card and a quarter of an inch thick. It's typically on the side of the laptop. You can insert a variety of devices into it, such as a Universal Mobile Telecommunications System card that gives you Internet access over cellphone networks.

Until recently, the cleverest device I saw created for this slot was the Mogo Mouse, which expands from its flat configuration to an actual wireless computer mouse. But I think the Vo200 may just steal the crown or certainly share it with the Mogo.

When you eject the Vo200 from the PCMCIA slot, the bottom portion of the card flips open and mimics the shape of a telephone handset.

You speak into the flipped-open portion while holding the upper portion to your ear. The Vo200 communicates directly to your computer via the Bluetooth wireless standard in much the same way as those wireless earphones work.

Hands-free mode

Buttons on the Vo200 let you select a convenient hands-free mode or talk privately by holding it up to your ear. The Vo200 also features an advanced echo-cancellation and noise-suppression technology that keeps your conversations clear, even in a noisy room.

When you return the Vo200 to your computer's PCMCIA slot, the Vo200 automatically recharges itself.

You'll know when to do that, as a blinking light warns when there's about 10 percent talk time left. However, you shouldn't be seeing that light too often because the Vo200 gives you more than three hours of talk time and up to 30 hours of standby.

The Vo200 is compatible with any PC running Windows and sells for $89.99. Just pop the Vo200 out of your laptop in front of a crowd and you'll have plenty to talk about.