The B-17 "Flying Fortress" is the bomber that was the signature Allied bomber of WWII. The B-24 "Liberator" was produced in larger numbers and had a larger payload and longer range, but the B-17 was somewhat more popular because of durability and significantly lower chance of catching fire in combat (surely a positive feature if you were flying in one, I'd imagine).
You can fly in B-17 for yourself. They're rattly and noisy, but you sure knew you were flying. The Liberty Foundation maintains a B-17 and sells flights on it. For flight nuts and WWII buffs, this sounds like a heckuva deal.