Some ideas are deadly.
This I set out to do, but so far no go. I thought that a feather couldn't kill anyone, but that turned out to be wrong. Then I tried a marshmallow. Unfortunately, it turns out that it can. A leaf, a sticky-note, a flower. I'm afraid I have to stop for the time being until I can tidy up here and then it's back to work.To make it more interesting I think people must backup their claims with evidences.
No, but we can provide examples for some. Bob said ice bullets. Not sure if it's even possible for them to exist, but how 'bout ice javelins: http://alloveralbany.com/archive/2009/01/13/death-by-icicleHow could that be possible? It's not like everything has killed someone.