The issue I have is that I have a few systems at my desk, and I use VNC to access them, so I only have one mouse/keyboard. What I'd like is a way to connect to the VNC server and not get video via VNC, but rather just use the system's CRT.
This involves two things: Mouse capture, and video disabling.
I think the easy way to do this would be to have a connection option to enable no-video mode, where you just get an empty window when you connect. Then you would press a hotkey to have the window capture the mouse. You could use the other system, then press the hotkey again to release the mouse. Keyboard usage is already transparent enough (Good work, btw!)
The "better" way would be to do something like the "x2vnc" project. You create a 1 pixel wide window at the edge of the desktop, when the mouse moves over that, you capture it, and activate the VNC session (again no video) Then you just track when the mouse moves in the other direction, and release it at the appropriate time.
I think this would take some discussion to sort out the fine details.