Kensington’s Dual Monitor Adapter ($119/£62) is an extremely useful gizmo that enables you to connect a second display to your computer using a USB 2.0 interface instead of D-Sub or DVI. Powered by DisplayLink technology, the black box is a snap to use: connect it to your computer (laptop or desktop), hook up a DVI-compatible monitor, install the driver software, wait for reboot, and you’ve then got two displays. It even works with an older analogue display using the supplied DVI-to-VGA adapter.

DisplayLink is a new technology that allows you to connect multiple monitors to one computer without requiring an extra graphics card, which is ideal for laptops. Supported on machines running Windows XP/Vista and Mac OS X, the innovative adapter works with any DVI or VGA monitor (widescreen or not). Up to six additional monitors can be connected to a single PC using multiple adapters. Disappointingly, the adapter only supports widescreen monitors up to 1440×900 pixels and standard monitors up to 1280×1024 pixels in 32 bit-colour, so those with high-resolution monitors will be frustrated. You can also choose from several display modes, including mirrored desktop, extended desktop and primary display, the tiny icon sitting in your taskbar lets you conveniently switch resolutions and change the virtual position of the extended desktop – to the left, right, top or bottom of your main screen.

A USB graphics adapter (UGA) such as Kensington’s Dual Monitor Adapter is the most affordable way to experience the plug and display simplicity of DisplayLink technology. UGAs provide the simplicity of USB to enable a simple external monitor connection, allowing you to quickly connect and enjoy an additional display to a PC or laptop. The ability to run multiple displays without the need for complicated and expensive hardware is now a reality. Sure, desktop users can set up a multi-monitor system by adding on an extra graphics card, but laptop users have always been limited to just the one extra display. It’s also more feasible for laptop users to have this kind of setup since the hardware is now more mature with dual core processors, dedicated GPUs and plenty of RAM. There’s now no reason why laptops can’t or shouldn’t be able to drive extra displays.

Kensington’s Dual Monitor Adapter is a low-cost way to add a second display. Ideal for laptop users not wanting a raft of features (there are similar products costing twice as much that offer a lot more flexibility), it provides a halfway decent video card that allows you to extend your desktop and get more productivity (and fun) from you machine. Don’t go trying to play any graphic-intensive games on it though, you’ll be sadly disappointed. It also needs a fairly powerful CPU to work well: Kensington recommends at least a 1.2GHz dual-core CPU. It may lack frills and support for high resolutions, but this USB adapter expands your desktop across an extra monitor for a surprisingly small price.