Meh...Nunchaku.

[Steve_TPF]

Aside from the fact that in most places it is illegal to carry them around with you.
Training with a weapon only has novelty value unless it's something you can legally carry, or you are attacked in your home (in which case you might as well grab a shotgun.)

I train in LaCanne, which uses a walking stick. A sturdy umbrella can also suffice. A belt can also be used as a weapon - something completely neglected by most styles (hapkido being a notable exception.)