How to switch between programs on different workspaces in Ubuntu (with Unity)

One of the things I always customise when using the LXDE desktop environment is to get alt-tab to not only change programs on one desktop/work space, but on all of them. On Unity I was looking for a way to do the same and discovered that I don’t need to change anything, there is aleady a built-in keyboard shortcut: ctrl-alt-tab. Although slightly more akward than just alt-tab, it works.