Acceleration of the thought process where in speech the ideas expressed crowd in with incredible speed. Most common in mania, but also found in schizophrenic disorders. The character Jeffrey played by Brad Pitt in the film Twelve Monkeys shows this nicely in the first scene in the hospital.
This noder suffered from flight of ideas intermittently for several years, and when it came he would write things down, over a few years these tracts became an autobiographical novel, which he never tried to get published, and now just sits on a CD on a shelf. At the time of generating the ideas seem rich and deeply meaningful, but when examined dispassionately later they turn out to be rather mediocre philosophical ramblings.