Application 1017

I have built dozens of contraptions and mechanisms utilizing pistons, D and T flip flops, AND gates, OR gates and XOR gates. I have three big, completed projects that I have done using redstone: 1. An entire city of redstone that explains how every single gate accompanied with truth tables. In the city is a two-faced, working clock with hands. This clock is around 100x100 blocks big and measured minecraft time with hardly no slowing or speeding. It uses 12 T-flip flops, 12 AND gates and hundreds of diodes. 2. a securtiy system(doorbell, lever lock and alarm system combined). Here is a youtube video of it in action and describes its anatomy: http://www.youtube.com/watch?v=OrxHZQg-KpI 3. a rollercoaster that has some twists and turns as well as some redstone applications to it. This is an awesome ride! Here is a youtube video of this as well: http://www.youtube.com/watch?v=h6sIUy1FH54 NOTE: for the part where there is bedrock, I used rail pressure plates and diodes for the lighting sequence. As for the surprise door I used 2 RS Latches and rail pressure plates.