Who needs coal to power your furnace, when you can just turn a redstone-reactive crank and cook your stacks of goodies? SethBling's hand-powered furnace lets you do exactly that, and it's pretty awesome! Of course, trying to put normal combustibles in the fuel slot has an unfortunate side-effect (it ends up in the void), but that's a small price to pay for what is essentially fuel-free cooking.
Don't forget: tomorrow (Tuesday, April 14th, 8:00-12:00 CEST) there will be a window of mandatory maintenance for Minecraft servers and databases. During this maintenance, you will not be able to log into Minecraft services, including playing multiplayer! Offline play will still work normally.