If you wish to remove the bottom panel in Gnome Shell fallback; you may achieve this by using the dconf-editor. Open it up and navigate to org->gnome->gnome-panel>layout and change the value from [‘top-panel’,’bottom-panel’] to [‘top-panel’] and then hit the ENTER key. This will make the bottom panel disappear. This is a very good way to free up some screen real-estate on a smaller screen. I am using Cairo-Dock so I do not need the task-bar. This is a very cool tip indeed.