An inclination calculation apparatus sequentially calculates an inclination of an input device operable in terms of a posture thereof. The input device includes acceleration detection means and imaging means. The inclination calculation apparatus sequentially calculates first inclination information...http://www.google.ca/patents/US7877224?utm_source=gb-gplus-sharePatent US7877224 - Inclination calculation apparatus and inclination calculation program, and game apparatus and game program
