Eh....you can't.
I was told that there was
something planned for them, but I've yet to see just what these items would be used for.
Well, if you want to use them THAT desperately, here's a few suggestions:
1. Poke random critters, like stray dogs and cats you see in the street. Don't worry...I hear they love it.
2. You can use them to stir your coffee. Try not to use your halberd to do that, though. Kinda gives it that weird, metally taste....
3. Climb into the lion's cage in the Empire Valley Zoo and poke the lions with your sharpest weapons. Go on, try it. It's FUN.
4. Use them to eat your ramen with if you don't have any forks lying around. Just try not to put your eye out...
5. Pretend you're a Dynasty Warrior!
6. Go up on a flyover [the first one leading to the Maritime Center is an EXCELLENT place], and toss those stones on passing cars. Hey...you
did find a use for them? Right? RIGHT?
P.S.: Be sure to aim for those white and blue cars with the sirens. I hear they give you tickets to the policeman's ball if you do that.
7. Commit Hari-Kari. Then get some serious medical attention.
8. Give them to me. NEO could always use them....[I'm not gonna tell you what for, though. Let's just say that it involves a bowling ball, a rabid hamster and some tapioca pudding and leave it at that. S'orite?]
9. Use them as a coatrack to hang up your hat....or something.
10. Sell them for gold. Then, cheerfully donate your gold to NEO. NEO will then be your friend. As long as you give him gold, that is....
Well, there you have it.
10 whole uses for your hard-earned weapons.
Now you can't say that NEO never did anything for ya.
Just follow those uses, [especially 8 and 10], and you'll have lots of fun!
....not to mention several lawsuits, but hey. What's public image compared to personal pleasure? Right? RIGHT?!!! 
