Potato Gun + Candy = Candy Gun. This is just too funny, it shoots all the candy up in the air for the kids to get. There are quiet a few different PVC parts for this so its not a simple build, but do’able by the average DIY person. I can see this being a big hit with kids.
http://www.instructables.com/id/Its-Raining-Chocolate-How-to-Make-Your-Own-Pneum/