Good morning Unityrs,
I know this topic has been already discussed but i can’t find the threads. Can anybody direct me to how is it possible to run more instances of unity3D 3.0 so I can have 2 projects open?
Thanks,
Giancarlo 
On OS X, you can start a second process by going to the unity application, show package contents, and fire up the MacOS/Unity executable. Don’t know about Windows.
On Windows you can launch multiple if you launch the Unity application and have “Show Project Wizard at Startup” (set in preferences). If you double click a scene it tries to load it in the open instance of Unity.
Brilliant guys! Thanks you sooooooooo much!