Does this sound familiar? Your mobile phone, your smart phone and your notebook all come equipped with Bluetooth, but you hardly use it because other than a clunky headset, there's not much to connect to. That may have been true in the past, but while you weren't looking, an array of cool and useful Bluetooth devices has appeared on the scene.

Named after 10th-century King Harald Bluetooth, who was temporarily able to unite several warring Scandinavian tribes, Bluetooth is a protocol for short-range wireless communications. The technology was released in 1999 but was slow to catch on, hampered by high prices and incompatibility problems among the devices that made use of it.

But accessory and radio makers have spent nearly a decade getting Bluetooth devices to play nicely, and the technology is enjoying newfound popularity among the mobile crowd. Casey Holmes, an analyst at VDC Research Group Inc. in Natick, Mass., predicts that sales of Bluetooth accessories could rise from US$1.6 billion in 2007 to $6.4 billion in 2011.

While Version 2.1 is the most recent Bluetooth specification, most of the devices on the market today haven't caught up. Not to worry: Bluetooth 2.0 products will reliably work together with hassle-free setup.

To get an idea of what Bluetooth is capable of these days, I tested 10 wireless accessories that help with everything from making hands-free calls and printing cell phone photos to typing e-mails and controlling presentations. I used these gadgets with a Sony Ericsson W580i phone, an HP iPAQ RX-1950 handheld and an HP Pavilion dv5000 notebook, all with built-in Bluetooth.

These gadgets were quick starters -- with a couple of exceptions, there was no software to load. And unlike in the past, all the devices were up and running in a matter of minutes, most on the first try. All of which means these accessories can free you from the tyranny of cables with almost no effort on your part -- though you should take a few security precautions.

The key to mobility: Logitech diNovo Mini keyboard

There are few things more annoying than the tiny keys or on-screen keyboards that make typing a tedious and not particularly accurate chore on smart phones and handhelds. Logitech's US$150 diNovo Mini keyboard can make every keystroke count -- and it can even make watching TV more relaxing.

At 5.8 ounces and about an inch thick, the diNovo Mini has a basic QWERTY keyboard with 63 keys, though it lacks the familiar Function and tilde (~) keys. While the 9.25mm keys may appear skimpy compared to a notebook's, they're twice the size of BlackBerry keys, and the backlighting makes typing in low light a snap. There's a responsive circular touchpad and keys for Page Up and Page Down, as well as buttons to control your Media Center PC from your favorite couch.

The diNovo Mini comes with a USB Bluetooth radio, but I didn't need to use it because the keyboard connected on the first try with my iPAQ handheld, my Pavilion dv5000 notebook and a Pavilion HDX Media Center PC. Within a few minutes I was typing notes, e-mails and spreadsheets, and was able to tap out about 20 words a minute, regardless of whether I was using my thumbs or index fingers. The keyboard had a 45-foot range and its battery ran for two weeks of on-and-off use.

As good as the diNovo Mini is as a go-anywhere keyboard, it really comes into its own for couch potatoes. If you've hooked up your TV to a Windows Media Center PC, the Mini provides an elegant, compact way to control your entertainment from across the room. It not only plays, pauses and moves tracks for CDs or DVDs, but it can adjust the volume and mute the sound. The best part is that it can nudge the channel up and down, or you can just type in the channel directly. The diNovo Mini is also compatible with the PlayStation 3 game system.

Whether you're vegging out in the living room or taking care of business on the road, it's the perfect wireless keyboard.