One of the more radical fighters the Germans came up with in the end of WWII, the Messerschmitt Me 163, called the Komet (Comet), was the first rocket-powered fighter to enter production. It looks quite ridiculous; in fact, it almost looks like a child's toy.  It had no true undercarriage; instead it had a two-wheeled "dolly" that was jettisoned upon takeoff. It would climb upwards rapidly and steeply, then the pilot would cut off the engine and it would glide down and open fire on any Allied bombers it comes upon on the way down. Amazingly, it actually was recorded to have made 16 air kills, but unfortunately those are not without losses, as the volatile rocket fuel components would sometimes ignite upon hard landings, causing the Komet to explode into flames, taking its pilot with it.  

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