DonM435 wrote:
THE GIANT SPIDER INVASION had notably awful effects, people wrestling with immobile mock-ups (long before Landau and Ed's Octopus). The biggest spider was played by a Volkswagen in unconvincing disguise.

The funniest thing about the full sized spider was the contempt the "extras" seemed to have for it. I saw the movie a long time ago but I seem to remember people throwing beer cans or such at the monster and running away laughing.