Hot process soap? It's old fashioned soap, but you warm the oils on the oven so that the process moves along faster. You mix fats and lye, stir until it is ready, then add colorants or fragrances. Pour in a mold, cut the next day, and voila! They make great, fairly inexpensive gifts, too. Only downside is that lye isn't available in grocery stores anymore, so you would need or order or find a chemical supply house locally.
Don't let the chemicals scare you - it is really easy. Just make sure to dress properly and get a cheap pair of gloves and safety goggles for while you're getting it down to a science.