Since i do not see any such instances on this thread , i would like to say that my Unity works in 3D on a laptop that has Optimus technology running on it. I have an NVIDIA 525M GPU and an Intel HD 3000 graphics card (i915?) . I am using NVIDiA drivers for CUDA , with bumblebee , and while installation , it was not allowed to config my display (no Xorg was created) .So essentially my Unity is running on my intel drivers ( i915 drivers that are available from the ubuntu repository. U can get this from software center) . I was having problems with this earlier since ubuntu dint seem to detect certain settings for Unity , but its running fine after an update (automatic) on some glx packages.
For some reason , /usr/lib/unity_support_test doesnt run now , and i cannot give you details on what were missing earlier.
But i thought that this might be useful to someone.