My pretty awesome vending machine I made, customizable currency and has a auto restock feature + a currency pickup place.
My very efficient TNT cannon, shoots 39 pieces of TNT.I've had other TNT cannons, and they've shot up too 1,152 pieces of tnt in one load (also very easy to make and VERY efficient).
Guys.Look at the SMP3 live map of town. Nearish the top right, a giant structure "You must be diamond" or something...lol.