My final project is a multi-thermal-control (and transportation) box. It is basically a plate whith different areas.
The user can fix the target temperature of each area, and the system will automatically do PID to reach those target temperatures.
Such a plate would be usefull in many scientific instrumentations set-up, where it is critical to thermalise differents parts of a system at different temperature, with accuracy and whithout thermal cross-talk.
On my
final project page, you can see how I came to need such a plate for my LED-based spectrometer.