@ariadnevery often. On gnome it's either that, an off-by-default widget, or a hot-corner (bleh) to launch the application menu (Which I'm perfectly fine with. I spend the vast majority of my time either in applications or in a terminal, so "press key, start typing" is perfectly natural and much faster than navigating a "start menu."). It also shows all open windows, so is quite useful for finding "hiding" modals that popped open behind other windows.