This is the zombie containment unit Halloween prop built by Roy Mueller using kits purchased from Hi-Rez Designs (who sell the DVDs with the animations, relay controller, as well as the pnuematics and water cannon effects -- you build the box yourself). When the zombie bangs on the sides they bulge, and when shit really goes south the box sprays toxic gas (technically water but I would add some hydrogen sulfide for a nice rotten egg smell). I love people that are so hardcore about Halloween. Halloween is probably my third favorite holiday behind Christmas and my birthday. "Your birthday is not a holiday." Well to me it is. I used to have this neighbor who threw these insane Halloween parties but the cops would always get called because I would call them because I'm 80 and get off my lawn.
Keep going for the worthwhile video.
Thanks to Shane F, who's going to be a zombie circus ringleader for Halloween this year, I can feel it. I have a gift.