Them (the movie not Van Morrison's group) was also a fave of min. Something about giant bugs I guess.

That old cold war radioactivity thing was a popular theme.

I am suprised that no one has mentioned the whole area of Japanese monster movies, featuring of course:

Godzilla
Rodan
Mothra
Ghidra the Three Headed Monster
That flying spinning giant turtle, what was it's name?