In Unity 2D there isn't any multiple workspaces. How can add more than that 1?
Update: Unity 2D now has workspaces, see this Omg!Ubuntu! post for more info.
From the Unity 2D announcement blog post:
Unity 2D does not yet support workspaces, but it will in the near future.
Update for GUI solution
Unity-2D with 4 workspaces (default)
Change the number of workspaces
Restart metacity so changes take affect.
Alt+F2, then type in
Your computer will have a temporary seizure, then it will be back to normal - but with added workspaces!
Unity-2D workplace-switcher using 6 workspaces
Execute in terminal:
where you replace
Not sure if this is a very recent change, but my Unity 2D supports workspaces. I don't have the 'Workspace Switcher', as referenced in DoR's response, but I do have workspaces. I navigate them via hot keys I setup in 'Keyboard Shortcuts'.