The Self-Propelled monorail is a machine that can be designed using pistons and redstone circuitry. By putting two sticky pistons pointing at each other and powering them alternatingly, they push each other along. If we have two pistons A and B, and we are moving in the direction that A is pointing, then we use this squence: A is powered, then unpowered. B is powerded then unpowered. This can continue indefinitly, as long as there is track to power them. Though they are not as fast as other ground transport technology, they are cheaper than minecarts and are good for moving large volumes of loot, or even whole trains of blocks.