Complete list of ggplot2's primitives is given by geom_*: blank(), path(), ribbon(), polygon(), segment(), rect(), text(), and point(). Every primitive starts with geom_* but not every geom_* is a primitive. In fact, the better odds stands for quite the opposite.
More or less, geom_blank() seems to be the simplest of the primitives. Calling it right after setting ggplot() will display a blank plot with axis already adjusted. It's mostly used to check axes limits given by data itself. Maybe you can find it useful for another task; suit yourself.
Other primitives may work in a similar way. That is the case for geom_path(), geom_ribbon(), and geom_polygon() functions. The first one draws lines between coordinates, second one ...
