『おまけ モモタロスのなつやすみ』は、2007年8月4日から全国東映系で『劇場版 仮面ライダー電王 俺、誕生!』と『電影版 獣拳戦隊ゲキレンジャー ネイネイ!ホウホウ!香港大決戦』と同時上映された『仮面ライダー電王』のスピンオフ作品。 マスター・シャーフーに泳げないことを指摘されたモモタロスは、ウラタロス・キンタロス・リュウタロス・デネブによる特訓を受けることになる。
Momotaros' Summer Vacation (モモタロスのなつやすみ, Momotarosu no Natsu Yasumi), abbreviated as Momo Natsu (モモなつ) is a short film that debuted between Juken Sentai Gekiranger: Nei-Nei! Hou-Hou! Hong Kong Decisive BattleIcon-crosswiki.png and Kamen Rider Den-O: I'm Born!. Using live action photographs, 3D computer graphics, and traditional animation (all of which is termed a Momotion Picture (モモーションピクチャー, Momōshon Pikuchā) by the production team), it has Momotaros gloating of his strength until Master Sha-FuIcon-crosswiki.png dared him to prove it by swimming. After being made fun of by Urataros and Ryutaros, and bashed by Kintaros, Momotaros is talked into believing he can swim by Deneb. But as the "mind over matter" influence wears off, the Imagin and Master Sha-FuIcon-crosswiki.png of the Gekirangers tell the audience the movie's coming up soon.
