While I love Blow Molds, I do have a particular decoration that gets me good. The pic at the top of this post is actually my single favorite Halloween decoration of all time. We had it hanging on our door when I was a kid. It's like crumbled plastic formed to make this pumpkin. Like you might see done with tissue paper. Not only did I find the one we had as a kid on eBay, but I also found that he had friends. Ghosts and Cats and Witches. I'm still on the hunt, but I'm overjoyed to know that they weren't all destroyed and melted down.
One last thing... I have a motion sensor pumpkin that makes a fairly common shriek/music when you walk by it. I love him. It was my mother's and she gave it to me when she outgrew it. I still search out other decorations that use the same, common sound effects. It's the perfect Halloween audio experience for me (except maybe the Chilling, Thrilling Sounds of Halloween from Disney).
Here are a few of my favorite Blow Molds. These are not mine.