Entertaining the Depths of Myth and Wisdom
Alaskan Bullworm - Spongebob Squarepants
I think there was a scene in Nemo where the fish were in a whales mouth chilling for a bit. Another scene is the main worm scene in Star Wars.
Luke inside the beast of burden's belly at the start of Return of the Jedi - when it keeps him warm.
Limbo in "Inception"