Humberto from Nerd Kits has built a DIY Sous-Vide Cooker. They are not touching any high voltage with their design, instead they are using a dimmer switch to power a crock pot and simply turn the dimmer switch with a small motor that is controlled using a microcontroller. A few small temperature sensors provide feedback so that the water bath temperature can be kept at the desired level. We have seen this method of interfacing with high voltage before with the Adafruit soldering skillet design.
