If you've seen a Sho Kosugi ninja movia, then you're familiar with the idea that ninja were sneaky blokes who hid weapons all over their bodies and sometimes disguised them in everyday objects. But what many people don't realize is that the samurai had a touch of sneakiness about them also.
Don't believe me? Well, here's a video showing a small collection of "secret" samurai weapons. It doesn't even scratch the surface of the small items samurai carried around to commit mayhem. If you're interested in learning more about these tools (and what that "cigarette case" really is), I can recommend this book by Serge Mol.