I'll start, my royal family does not pass down crowns or swords instead, the Holy Hand Grenade:
Background:
...And Saint Attila raised the hand grenade up on high, saying, "O Lord, bless this Thy hand grenade that with it Thou mayest blow Thine enemies to tiny bits, in Thy mercy." And the Lord did grin and the people did feast upon the lambs and sloths and carp and anchovies and orangutans and breakfast cereals, and fruit bats and large chu...
This prized relic is now in posession of our Lady of New Pittsbugh, Queen of Israslovakahzerbajan and it's Commomwealths, Yukari Tanizaki I.