Alright so maybe I'm just a little slow on the uptake on this one but I was creating a house for a new character from stuff from some of my other characters, ya know, so he would be born with a silver spoon so to speak, when the idea dawned on me... I could have secret exits (not from people obviously the switches give it away, but from zombies knocking my door in) Now I know that there are easier tricks, lifting your door just off the ground and etc, but this one seems so much cooler to me. So here are some pics to explain what I am talking about. I have wired a three way switch (because I have one in my house, and one exit on either side) to some active block and some dungeon lights. I love it. Sorry if everyone else has already thought about this :).
Secret tunnel1

In my house, secret tunnel off

Secret tunnel2

In my house, secret tunnel on.

Secret tunnel3

Secret tunnel exit open

Secret tunnel4

secret tunnel exit closed