If they aren't broken, why change your current keyboard or mouse arrangements?

Well, laptop owners often feel they'd like the extra space a full-sized desktop keyboard offers, and a mouse can be a lot easier for some people to use than a laptop's integrated controls. Then there is the fact that, for both desktop and laptop owners, add-on keyboards can offer a host of extra keys for doing a lot more than just tapping out text.

And finally, there is ergonomics. Yours truly has been using the same ergonomic keyboard for nearly ten years. Its QWERTY keys are separated into two clusters and ranged at an angle to each other. It might sound weird, but it is very comfortable and I believe it is good for preventing RSI too.

Logitech combines a different ergonomic arrangement and multitude of buttons with wireless access in its Cordless Desktop Wave keyboard, which comes with a wireless optical mouse.

Both elements are powered by two AA batteries. Getting up and running is simplicity itself. Step 1: insert the batteries. Step 2: laptop users drop the wireless dongle into a spare USB socket, desktop users plug a USB extension cable into the computer case and then slot the dongle into the dock this places on your desk. Step 3: press the connect buttons on the dongle, keyboard and mouse.

Unfortunately in each case the connect buttons are on the underside. This is most irritating with the dongle. If it fits into a horizontally mounted USB slot rather than a vertically mounted one, finding the tiny connect button puts undue stress on the USB slot.

The keyboard ergonomics amount to the fact that a horizontal bevel raises the QWERTY keys in a sort of wave pattern (get it?) so that the central and outer keys are at the high point, the inner ones lower down. This, says Logitech, mirrors finger length and should make typing more comfortable - if, that is, you touch-type and your fingers are hitting the keys they should. There is also a 5-degree curve in the horizontal arrangement of keys which means you don't have to bend your wrist awkwardly when typing.

A very nice padded wrist-rest is below the keys, and a full-sized number pad sits to the right side. Its numbers are arranged in a standard configuration; no waving here. Ditto the bay of cursor control, Home, End and Delete keys, though the general size of these keys has been nicely thought through with a tall, thin Delete key opposite the oversized Enter key.

The 12 function keys can be programmed to launch applications, folders or Web pages if you install the accompanying software. Meanwhile, buttons ranged around the top and left side of the keyboard give access to various aspects of your computer. Windows Vista features like Photo Gallery and Gadgets are a shortcut key away and there's a panel for volume control and music playback. You can even turn the computer off by tapping a dedicated key.

Feet on the underside of the keyboard give you a choice of two raised angles or you can have the keyboard flat to the desk.

In use the keyboard has a rather nice springy feel, and touch-typing at speed was not a problem. The wave effect is quite subtle, and did not feel as ergonomically sound as my ‘split' keyboard, but that may be because I am very used to the old keyboard and the Wave idea is new. I can't say whether one is actually better for you than the other.

As keyboards go the Wave is necessarily chunky. But its added buttons are large and many of them have features I'd deem useful. You might want to try the keyboard out before buying if you are drawn to it, though, just to see if the Wave effect works for you.