Lenovo have quietly launched a USB to DVI monitor adapter based on DisplayLink's virtual video card technology, that promises up to 1,920 x 1,200 WUXGA output - supporting 1080p High-Definition video - via a single USB connection. Up to six of the adapters can be used on a single computer (three if you have a ThinkPad with switchable graphics) in addition to the machines' native video outputs.
As with other DisplayLink systems we've seen, the Lenovo adapter requires no rebooting once plugged in, supports full rotation (in 90-degree increments) and 8- to 32-bit color depth. It's also powered from the USB bus, so no extra AC adapter is required.
Currently available for $129 from Lenovo's own online store, it's a reasonably straightforward way to add a few more displays to your notebook. Remember, though, that the virtual graphics card will have an impact on your CPU performance, and that impact only gets bigger as you add more adapters.