In 1992, President Alberto Fujimori of Peru, frustrated by an obstructionist Congress stymieing his every effort to battle both hyperinflation and the psychotic Maoist Shining Path insurgency, suspended Peru's constitution, granted all legislative powers to the executive branch of government and sent the Army to seize all members of the Congress opposed to him. For his use of the Army to lead a toppling of the constitutional order of which he supposedly was the apex, leaving himself in power, Fujimori was credited with having pioneered, or at least provided the textbook example of, a new form of government overthrow, the autogolpe or auto-coup.
Hatoyama Yukio deserves a similar honor for what he achieved on June 2 - 4. The newspapers have for the most part referred to what happen as Hatoyama's having "stepped down" (taijin - literally "withdrawal of the military encampment") from the post of prime minister - the standard term for a prime minister resigning voluntarily. However, in overseeing a friendly transfer of power to his fellow party co-founder Kan Naoto, securing the bloodless simultaneous political seppuku of his supposed political master Ozawa Ichiro, all with the retention of his entire Cabinet save four of the five really problematic/ferociously unpopular ministers and party executives (himself, Ozawa, Consumer Affairs Minister and Social Democratic Party leader Fukushima Mizuho and the Miyazaki Foot-and-Mouth Disease outbreak scapegoat Akamatsu Hirotaka. The fifth problematic minister, Financial Services Minister and People's New Party leader Kamei Shizuka, was left behind for disposal by Kan) Hatoyama should be considered the author of a political innovation worthy of its own technical term. For what happened was not so much a change of Cabinet as a Cabinet reshuffle, only one where the Prime Minister, realizing that he is part of the problem, reshuffles himself out of the Cabinet lineup.
Perhaps it should be called "The Pigeon Mountain Shuffle" -- that seems to be a sufficiently "loopy" name.