I have reopened the Unity launcher by disabling auto-hide, thanks to this post -- https://askubuntu.com/a/106673/42720
I am running 12.04 in VirtualBox, and have tested this in both full-screen and windowed mode. Moving the mouse to the left side, or top-left corner, of the Ubuntu desktop does not make the Unity launcher reappear. I'd really like to be able to use this feature because I have a small laptop monitor.
Any ideas? Thanks