i bought one for 49 € at http://www.pearl.de.
it is a wonderful device for remoting a camera.
currently i’m using it with GlovePIE which is a little bit itchy sometimes.
after experiencing @velcrome wonderful wiimote-plugin i can imagine a spacenavigator plugin working perfect.
unfortunately i am not able to write plugins with c# myself by now.
the missing buttons can be done with a GameController (Devices Analog) .
btw.:
the attached camera feels like an advertisement for that device…
really pure fun.
now you can use the mouse for the essential things…
the attached camera is completely compatible to the Camera (Transform Softimage).
So you can still use the wellknown shortcuts to control the camera even when you forgot your spacenavigator at home…