Did know one mention THE BEAST FROM 20,000 FATHOMS? I just saw it recently at a theatre where Ray Harryhausen spoke before the film. It held up better than expected: not only were the effects entertaining, but the film had a decent script and did a good job of holding interest even when the monster was not on screen.
You can see a video of Harryhausen's talk here:
http://hollywoodgothique.com/beastfr...thoms1953.html