Reflow soldering is common technique of soldering SMT parts to PCB. This is quick process, but requires precise temperature and timing control. If you are about to build/use one, be sure to implement controller that would take care of heating and cooling process. 0xPIT shared his reflow oven controller project where he did really good job on functionality and looks.
Controller is based on Arduino Pro Micro which sits on top of custom made motherboard. Motherboard performs load switching by using PSB-mount solid state relays and interfaces thermocouples with MAX31855. Software is based on PID algorithm which gives smooth control of heater and fan. But probably the color LCD is that catches eye at first. It displays information in nice graph. Intuitive menu allows selecting parameters like fan speed, PID constants and more. This is great example of paying attention to details when you are serious about where controller is gonna be used.