Let's say I have a PC with two monitors atached. I'm running e.g. Windows Vista natively, and start up a virtual Ubuntu PC. I change to fullscreen mode so that on one Monitor, I see my Windows Desktop, and on the other one, the Ubuntu Desktop. I can now use my mouse and Keybord for both of them.
This works fine, but I'd really like to connect a second mouse and a second keyboard to my physical PC, and do some configuration so that one set of input devices is used for Windows, and another set for the virtual Ubuntu. Then two persons could work at the same time, as if they were using two separate computers, although there is only one physical machine.
I'm currently using Sun VirtualBox and it has a feature to assign specific USB devices to the virtual machine. While this sometimes works for e.g. external disk drives, it never worked for mice and keyboards for me (yes, of course my input devices are attached via USB!).
I'd like to know a solution that works with VirtualBox, but any answer is appreciated, even if another virtualization software or some additional hardware was needed.