What to do when Unity's Launcher gets stuck open?

My Unity Launcher is currently stuck open. Short of logging out and back in, does anyone have ideas for getting it to auto-hide as usual?

It turns out that the Launcher is supposed to stay open on workspaces containing no windows. Two of my workspaces had maximised windows which Unity didn't seem to be noticing, and when I closed those and then re-opened them, the Launcher reverted to its correct auto-hide behaviour.

Perhaps one could also simply move the window to another workspace and back to get the Launcher unstuck--I did not think to try that.

None of the methods above like Super S/Super-W, drag drops, min/max/move windows worked for me.

Only running ccsm, disabling Ubuntu Unity Plugin, and re-enabling it.

Ubuntu 11.10