User:MentalMouse42/Sandbox/Misc Diagrams 1

Tiny Charcoal Generator
Source]

It's supposed to feed its product back into the furnace to fuel itself. However, it was an April 1 (2013) posting, so it warrants testing. At first test: Looks like it will not accumulate any charcoal in the chest until both the furnace and the hopper feeding it fuel (level 2) are full. The hopper can be "stuffed" with four non-fuel items in its last four slots, as long as you leave the first slot open for fuel. Then the chest will start getting charcoal after two stacks of charcoal are produced, which will require 2-$1/4$ stacks of wood.

If more than 5-6 stacks of wood are available, another chest can be placed atop the upper hopper.

As usual, using a hopper to take product from a furnace forfeits any experience from the smelting.

cobblestone generator
Earliest Known Publication: May 29, 2012 This circuit can be built in a 4&times;5&times;2 hole, with two blocks dug out of the bottom (level 0), and the clock extending two blocks out from one corner.

The upward facing piston is on level 0. The hole east of it contains redstone and is covered by any transparent block (glass shown for visibility). The redstone torch in the main section is temporary; once you've built the clock, place a lever on either input block (green wool), and flip the lever, then replace the torch with redstone dust. Note that the lever is turning the clock off, so turning the lever on will stop the generator.

At this point, you can run the generator, or do a bit of tidying-up: The rest of level 2 can be filled with any block, and you may want to cover the lava (and even the exposed repeater), with a slab.

Variation: Since the clock is already protruding, you might want to substitute a longer one to cut down on the piston noise. Experiment carefully with the delays, as some clock cycles can stop production entirely. (With this 5-clock, the generator is moving the pistons three times for every block.)