One of the least known, but most impressive aircraft of WWII was the Mosquito. The Mozzy was a two engined aircraft used throughout the war, mostly by the British. It was designed to be a bomber, but the Mosquito was built around the principle of being fast and light instead of slow, heavy, and well-armed like most of the bombers of WWII. It was powered by two Rolls-Royce Merlin engines and the plane's airframe was made mostly of wood.
The Mozzy was more often equipped as a night fighter or reconnaisance aircraft than a bomber. The RAF bomber command didn't think it could do normal bombing because it lacked gunner positions. Occasionally the Mozzy was used for precision bombing, special ops missions, and pathfinding for the heavies. Pathfinding meant the Mozzies would use their speed and superior accuracy to mark targets for the bigger slower Lancasters.
All this is a shame, because two Mosquitoes could carry the same bomb load as a Lancaster, but were cheaper, and required fewer crewmen. We now know that their precision means that they would also be more effective with their ordnance.
Oddly enough it was the Germans who saw the Mozzy's worth. At one point they remarked that British ingenuity had meant that their best bomber could be build by any carpenter or piano maker in his own garage.