You should make a large jumbo tron with redstone lamps. I did that for one of my videos and it wasn't too complicated. You could make one better but mine was rushed. You can see it by searching bdubs hotel in the minecraft forums video search.
Hey, I got some of my own ideas I want to give you with redstone, easy and hard.
1. Emerald Machine; make a machine that if you add a minecart in it, it will give you an Emerald, or whatever else you want, through a dispenser. Easy to make. By the way, I got no screenshots now, but if you chose a nice idea, I will post a screenshot to help you.
2. Cobblestone Generator; use lava and water in the right way to get cobblestone, but use some pistons and redstone to push the cobs into a repository. kinda easy to make.
3. Casino; use the Emerald Machine for the awards you get, and make the games by your own, like riding minecarts and you have to hit them with arrows. exchange the minecarts in the machine, and maybe for extra, add different awards, from wheat to diamonds. depends on how much games, but I will suggest its a little hard.
4. I am still working on it, but maybe make a slot. I still got problems, and my brain is like exploding, so it is DIFFICULT but a great challenge
5. Meat factory; use dispencers and monster eggs, to give people fresh food, and let the animal, like a pig, die fast and maybe you got some own ideas to make it cooked already. this method will give you fresh food (it doesnt make any difference if you just put meat in dispencers, but it is more challenging.)