Mousing to the “hot corner” in Cinnamon gives an overview of current workspaces, à la expose. Unfortunately a careless click can close one of those workspaces, as I found out last night. Equally, you may feel that the default 2 workspaces is too few and wish to expand upon that. Now, I think the numvber of workspaces should increase automatically*, but it’s nice to control such things. Unfortunately there is no “control panel” option to control the number of virtual desktops, and right clicking the workspace changer widget in the toolbar doesn’t seem to have any useful effect.
However, hit Ctrl+Alt+Down and there should be a ‘+’ icon on the right hand side which will add as many workspaces as you require.
Update: Apparently the hot-corner expose has the plus to add workspaces too. I guess I just didn’t see it there! Cheers James.