You can make some small changes to the left launcher panel using the Ubuntu Unity Plugin. You can change the way the panel is hidden (never, Autohide, Dodge Windows or Dodge Active Windows). You can also change the way the panel or icons are highlighted when clicked on.
To make the changes you need to have ccsm (CompizConfig Settings Manager) installed. To install ccsm and the plugins open a terminal window (press Alt+F2 and type: gnome-terminal) and copy+paste the followin line:
sudo apt-get install compizconfig-settings-manager
When installed close the terminal window, press Alt+F2 and type: ccsm to open the CompizConfig Settings Manager.
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Scroll down until you see the Ubuntu Unity Plugin and click on it. To change the way the launcher hides click on the Hide Launcher button. To make changes to the way the panel and icons are highlighted click on the Experimental tab and play with the settings until you find the combination you like.