Biting

Biting in self-defense is actually very effective! Nothing fancy - but then again, fancy seldom works.
There have been a number of reports on people who used this method to avoid serious situations.

Story:
South Africa -- A policewoman has freed herself from a potential rapist by biting off his tongue.

The 40-year-old suspect, who works at a chain store in Bushbuckridge, was admitted to Mapulaneng hospital in Limpopo in a serious condition just before midnight on Monday.

The woman said the man had lured her into his house after they had been drinking together.

Source