Everyone has a "multibillion" dollar idea. It goes something like this:
"lets build a <current successful service> but better and for <niche group>". (e.g. "Lets build Facebook but for dogs." True story --
http://www.dogpawfile.com/ )
Chances are that none of "these brilliant ideas" are novel enough to be worth anything on their own. There's little value in the initial idea, as ideas change. That "next Facebook" idea for Facebook was "lets rate girls for hotness in our dorm". That's not value -- direction, leadership, capital,
execution are value.