Hidden dagger?

I kind of want to attach a dagger to this mechanism, even though it wouldn't be very practical, haha.

http://www.indymogul.com/backyard-fx/episode/BFX_20090119

Even if I could get it to work it probably wouldn't be allowed on the field.

Oh wow. XD Even if it isn't allowed, that's an amazing idea, hahaha.

I think you could do it, but it would have to be similar to a crossbow (have less than 15 lbs. of force when it pops) Very cool idea, and especially useful for spearmen.