Tom's Hardware Guide has a short description of the Tritton Technologies See2, a USB-to-SVGA adapter. It lets you expand your screen real estate by connecting a second monitor to your computer's USB port.
Data throughput limits mean that certain content such as streaming video are not supported by the See2, but the company says that things like Photoshop tool palettes can easily be displayed on the second screen. The See2 will list in the US for US$99, and will become available in September, according to the Tom's Hardware article.