No longer maintained.
Popcorn Smelting re-adds in-world smelting from Indev.
Drop an item in fire or lava, and it will be smelted.
Required on clients and servers, due to how it's implemented with a custom entity. Not easily fixed due to a lack of needed hooks in Forge, and I don't really want to add ASM to such a simple mod.
As of v1.3, CraftTweaker can be used to add Popcorn Smelting-specific recipes. The interface is identical to vanilla furnace recipes, except you must use "mods.popcornsmelting" instead of "furnace" for the method calls. There is also a config option to disable inheritance of vanilla furnace recipes.
For example:
mods.popcornsmelting.addRecipe(<minecraft:speckled_melon>, <minecraft:melon>, 1500);
30 second demo video with no voice