My boss has asked me to put together a sous vide rig. I'm starting this thread to document the process. Right now I'm at the selecting the features/specs stage. I'm going to make the control box modular so it can run a sous vide cooker, a smoker, a warmer for yogurts and cheese making, beer brewing, heck, even a bread proofer. The core elements are: The PID controller: This is the brains of the operation. I've pretty much decided on a JLD612 model. The Temp Sensor: I'm planning on going with a waterproof PT100 RTD temperature probe. It's a got a good accuracy and resolution that's made it standard in the DIY community. PID controllers only accept certain kinds of probes, so make sure they're compatible. I'm going to wire it into a TRS plug and socket (like a headphone jack) so the probe is not hard wired into the system. Single State Relay: It's the switch the controller operates that turns the heat source on and off. The JLD612 has an internal relay, but it's too small for our purposes. You'll need to get a heat sink for this component. With these core items and some odds and ends (project box, sockets, etc), you can build a basic sous vide device by hooking it up to a dumb rice cooker or a crockpot.