An AddOn which provides a number of key-bindable 'popup' action bars (that map to the high-numbered action slots). See the WoW key bindings menu to assign keys to open the bars. The bars operate in one of two modes:
1) Press and release the trigger key, it opens the bar then you can press one of 0-9 to perform an action and then the bar closes automatically (You can also press the trigger key again, or hit ESC to close it without performing an action)
2) Press and hold the trigger key, then use 0-9 to perform actions, the bar will remain open until you release the trigger key.
You can also use the /poplabel command to set a text label for the currently open bar.