The Entropy Manipulator
The Entropy Manipulator allows you to heat and cool things by right-clicking and shift-right-clicking respectively. It can't do much, just things like evaporating or freezing water, solidifying lava to obsidian, smelting logs to charcoal, and smelting cobble to stone in-world.
If there is not a specific thing it can do to a block, it will act as a flint-and-steel.
Its energy can be recharged in a Charger.