I just noticed that my Alt+F2 no longer works in GNOME Shell on Ubuntu 11.10. It was working fine just last week . How can I fix this?
This is an odd issue where the keyboard shortcut to show the run command prompt becomes unset. To set it again open System Settings, choose the Keyboard panel under Hardware, and open the Shortcuts tab. From there, you can find the shortcut in the System section, and set it by clicking in the right column.