Perhaps the most famous duel ever was between David and Goliath in which David defeats the much larger Goliath with a stone slung from a slingshot.
Other famous duels include those between:
Alexander Pushkin, the great Russian writer, and Georges d'Anthès, a French nobleman, in 1837 in which d'Anthès mortally wounded Pushkin, who was only 37.
While today, dueling no longer exists in our society we do have boxing which has had it share of famous "duels" over the years, such as: