Of course, I am a huge fan of Ray Harryhausen*, and I vividly remember seeing 7th Voyage of Sinbad in the theater when I was but a wee kid (scared the shit out of me). And, most would cite 7th Voyage or Jason and the Argonauts as his finest work. But my favorite Harryhausen film is Earth vs The Flying Saucers. I just love the corny and hilarious charm of this film, the creative use of stock footage and the clunky acting (especially the distorted “alien” voice of Paul Frees).
*Every person who was raised in the 1950s and grew up to become a Visual Effects artist is a fan of Ray Harryhausen, of course!