Tritton Technologies presents the See2 series USB external video card that allows you to an add additional display via USB 2.0 port. In total, there are four models supporting different resolutions.
The See2 Extreme (TRI-UV200) is top-of-the-line model with support for 1920×1200 Full HD resolution and does USB to DVI conversion. It works with both PC and Mac and includes a DVI to VGA adapter. The See2 UV150 (TRI-UV150) is also compaitble with Mac but supports resolution up to just 1600×1200. Next is the See2 (TRI-UV100) that handles 1600×1200 like the UV150 but works with PC only. Lastly, the See Express (TRI-UV50) supports only 1366×768 resolution.
The See2 UV150 and See2 Extreme are priced at $89.99 and $49.99 respectively.