Ick Barrier

Usually something important is guarded by an impenetrable barrier, such as a locked door, or isn't anywhere accessible at all. However sometimes in movies or video games we see things or passages where the only guardian is something everyday people find disgusting. This might be something that could prove dangerous, such as possibly venomous spiders or scorpions. However, sometimes it might be something that is merely disgusting. Sometimes it's not something living at all, such as slime or a subject of phobia where a character must overcome his fear.

Non-living examples would be a foul-smelling, slimy bog or a passageway covered in spider webs.

Film

 * Indiana Jones films:
 * The Well of Souls in Raiders of the Lost Ark.
 * Indiana Jones and The Temple of Doom: The lever to disable the death trap was covered in webs and insects. Real insects.
 * Indiana Jones and The Last Crusade: The horde of rats in the catacombs under Venice where the shield was hidden.
 * Labyrinth had the Bog of Eternal Stench.
 * Desperado had a secret passageway in a Bad Guy Bar hidden by a mechanism in a totally disgusting excrement-stained toilet.

Video Games

 * Inverted in Golden Sun, where the heroes are blocked from a certain path by a group of playing puppies that they don't want to disturb. Justified in that there's no immediate hurry and you're supposed to be going elsewhere, so there's no reason for them to insist on heading that way.

Literature

 * In Tarnsman of Gor, a secret passage into (and out of) the Central Cylander of Ar is hidden in a fake Dar-kosis pit - a place where sufferers of Dar-kosis (leprosy, more or less) are kept, away from the rest of civilization, until they die. The lever to open the door is further hidden in a disgusting, dank, scummy water sump within the DK pit.
 * Cirith Ungol in Lord of the Rings. The Watcher guarding the Gate of Moria, too.