I'm always on the lookout for new hardware that might be applied to video projection and Modul8.
A company called DisplayLink produces hardware that lets you add multiple video outputs via USB 2.0, and they've just released beta drivers for Intel Macs:
http://www.displaylink.com/mac_beta_drivers.html
Unfortunately, at this point the beta drivers lack 2D/3D(OpenGL) acceleration, so it is not yet usable for Modul8. However, they ask us to request improved support from Apple (and they provide a link to the Apple Feedback form) to work with them in providing access to the 2D/3D system. Please take a moment to do so. This is an interesting product that could really benefit the VJ community. Thanks!
Blair