7. Tomatoes (Attack of the Killer Tomatoes)
A high-level government conspiracy unleashes the wrath of fleshy fruit on the nation's unsuspecting populace.
Method of attack: Flinging themselves. Details of the method are a mystery left to movies with bigger budgets, but it manages to overwhelm everyone from lone housewives to the U.S. army.
How to defeat: Subdue with the song "Puberty Love," then stomp as needed. Warning: Humans are not immune to the song's ill effects.