Some of my ideas.
More often then not, however, that person will admit that they have simply been "tossing the ideas around in my head for awhile." Perhaps he or she has not had the time to try to flesh the idea out. Or perhaps it is simply too much of a risk to see if the ideas actually hold up to a playtest. As long as it is an "idea" that exists only in the imagination, it works (idea = ideal).