That would have been easy, as would have trapdoors been.
My plan is to have an extended piston holding back lava, when you press the wrong button, it retracts. The hard part was getting it to retract for long enough to allow lava through.
The insanely difficult next bit is to have it on multiple levels, where the right answer releases water instead of lava, and you can swim up through the water to reach the next level. I don't think that's feasible though unfortunately, it's going to be hard enough for one level!
Having said all that, some preople really do have too much time on their hands, but make awesome redstone stuff - see this piston-engined train for example:
http://www.youtube.com/watch?v=IzzxS_MP8sQ |
