Left 4 Dead Barricade Building

I've recently purchased Left 4 Dead 2 but there is one thing that keeps me coming back to the original Left 4 Dead... barricade building.
I'm just curious about how many people are familiar with this, and would possibly be able to share any tips. I've been able to create my own barricade builder by taking models from various barricade builders available online along with others that I was able to find in game.
However, I've seen people making objects that you can shoot to make them disappear and they reappear shortly after, which is great for doors n' stuff and also lights that are able to be turned on and off. Is anybody familiar with this or does anybody have some good models and tips might come in handy?


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I refuse to change this sig until I take a bath!
08/07/2007