Sword Cane
In Unusual Weapons
A swordstick or canesword is a cane incorporating a concealed blade. The term is typically used to describe European weapons from around the 18th century, but similar devices have been used throughout history. Note especially the Japanese shikomizue and the Ancient Roman dolon.
They are also very easily hidden. A swordstick may be illegal to carry in many jurisdictions. It is a concealed weapon, and is sometimes considered a disguised weapon.