Sous-vide cooking is a lot of fun. Food is vacuum sealed and cooked for many hours in a water bath at a specific temperature, usually something like 140°F, far below boiling. Meat becomes really juicy, eggs become creamy, and you can do all sorts of fun precision cooking. However, cookers on Amazon cost $100–200, which if you ask me, is a scam. I've also seen instructions online for Arduino-based cookers that use a relay to control a crock pot, but even those often cost something like $40 ...
